JP2020011399A - Optical protective film - Google Patents

Abstract

To provide an optical protective film which can suppress occurrence of a Newton ring phenomenon, and can improve luminance.SOLUTION: An optical protective film (10) includes a particle-containing layer (3) on one side of front and back surfaces of a base material film (1), in which a difference between reflectivity R2 of a film surface on an opposite side to the particle-containing layer (3) and reflectivity R1 on a side surface of the particle-containing layer (3) is more than 4%.SELECTED DRAWING: Figure 1

Description

  INDUSTRIAL APPLICABILITY The present invention provides an optical protective film that can be suitably used as a constituent member of a display device or the like, and in particular, an optical protective film that can be suitably used as a protective film for a phosphor sheet having a phosphor layer containing a phosphor. And a protective film.

In recent years, there has been a tendency to sharpen the emission spectrum of a backlight for the purpose of improving the definition of a liquid crystal display device and improving color reproducibility. For example, in Patent Literature 1, a white dot is reproduced between a blue LED light source and a light guide plate by using quantum dots that emit red light and green light as a phosphor, thereby achieving higher luminance and improved color reproducibility. Technology has been proposed.
As an example of a liquid crystal display device using such a quantum dot technology, a reflecting plate on which a blue LED is mounted and a resin sheet containing a quantum dot (also referred to as “QD”) as a phosphor are sequentially provided from the light source side. And a liquid crystal display device having a structure in which a prism sheet, a diffusion sheet, and a polarizing plate are laminated. Two or three types of quantum dots having different light emission characteristics are excited by light incident from the LED, and can realize white light.

  Incorporating a laminate in which a protective film is attached to the surface of a resin sheet containing a fluorescent material such as quantum dots into a display unit, the stripe pattern due to light interference, the so-called Newton's ring phenomenon, is likely to occur, especially in liquid crystal display devices. This was a serious technical problem in applications requiring high visibility.

  As a countermeasure to prevent the Newton ring phenomenon, for example, Patent Literature 2 proposes a method of preventing the Newton ring phenomenon by making the outer surface of a protective film bonded to the surface of a resin sheet containing a fluorescent substance uneven. .

  In Patent Literature 3, the problem of Newton's ring is improved by using a matte tone in which unevenness is imparted to the film surface, but the brightness of the liquid crystal display device tends to decrease due to light scattering on the uneven surface. In order to solve such a problem, a hard coating film on a transparent support is used as a matte optical film capable of preventing the display quality from deteriorating (display unevenness, luminance unevenness, etc.) without causing a reduction in display brightness. Characterized in that the hard coat layer comprises a crosslinked binder polymer and transparent fine particles, and has a surface roughness Ra of 0.1 to 0.3 μm and an Rz of 1 to 3 μm. Optical films have been proposed.

  In addition, Patent Document 4 includes a base film on at least one surface of a wavelength conversion layer including quantum dots in order to provide a wavelength conversion member with low light loss, and the base film is measured using an integrating sphere. A wavelength conversion member that has an absorptance of light having a wavelength of 450 nm of less than 0.9% and a total light transmittance of less than 92% has been proposed. Further, in order to provide a high-brightness backlight unit including a wavelength conversion member having a small light loss, a planar light source that emits primary light, the wavelength conversion member provided on the planar light source, A backlight unit including a retroreflective member disposed to face the planar light source with a wavelength conversion member interposed therebetween, and a reflection plate disposed to face the wavelength conversion member with the planar light source interposed therebetween, The wavelength conversion member emits the fluorescence using at least a part of the primary light emitted from the planar light source as the excitation light, and emits at least light including secondary light composed of the fluorescence. A backlight unit is proposed.

JP 2012-169271 A JP 2017-217919 A JP 2001-33625 A JP-A-2006-071341

As described above, when the surface of the protective film is made to have a matte tone by providing irregularities, the occurrence of the Newton ring phenomenon can be suppressed, but the brightness of the display device is reduced.
Therefore, an object of the present invention is to provide a new optical protective film that can suppress the occurrence of the Newton's ring phenomenon and can improve luminance.

  The present invention provides an optical protective film provided with a particle-containing layer on one of the front and back surfaces of a base film (1), in order to achieve the object, wherein the reflectance R2 of the film surface on the opposite side to the particle-containing layer is The present invention proposes an optical protective film characterized in that the difference from the reflectance R1 of the particle-containing layer-side surface is larger than 4%.

  The optical protective film proposed by the present invention is an optical protective film having a particle-containing layer on one of the front and back surfaces of a base film (1), and has a reflectance R2 of a film surface on the opposite side to the particle-containing layer. Has a special optical property that a difference between the reflectance and the reflectance R1 of the particle-containing layer side surface is larger than 4%. Therefore, the present invention can suppress the occurrence of the Newton ring phenomenon, and furthermore, the present invention proposes, for example, that the opposite side to the particle-containing layer is located on the phosphor sheet side on one side of the phosphor sheet. By disposing the optical protective film, the light incident on the particle-containing layer of the light emitted by the phosphor can be reflected to the phosphor sheet side, and the luminous efficiency of the phosphor can be increased. In addition, the luminance can be improved.

FIG. 1 is a cross-sectional view illustrating an example of an optical protective film according to an embodiment of the present invention. It is sectional drawing which showed the other example of the protective film for optics which concerns on the Example of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which showed an example of the optical film laminated body (wavelength conversion film laminated body) which concerns on the Example of this invention, and an example of the backlight using this. FIG. 4 is a cross-sectional view showing another example of the optical film laminate (wavelength conversion film laminate) according to the example of the present invention and an example of a backlight using the same. It is sectional drawing which showed an example of the structure which combined the example of the optical film laminated body (wavelength conversion film laminated body) which concerns on the Example of this invention, and the prism sheet.

  Next, the present invention will be described based on an embodiment. However, the present invention is not limited to the embodiment described below.

<<<< this protection film >>>
The optical protective film (referred to as “the present protective film”) according to an example of the embodiment of the present invention includes a particle-containing layer (referred to as “the present particle-containing film”) on the front and back surfaces of the base film (referred to as “the present base film”). A layer).

  The present protective film may have a configuration in which a particle-containing layer is provided on the front and back surfaces of the base film. For example, as shown in FIG. The particle-containing layer (3) may be provided on one side of the front and back surfaces of the base film (1), and the other side of the front and back surfaces of the base film (1) may be provided. It may have an asymmetric configuration with a base film (2) on the side. Further, as shown in FIG. 2, the present particle-containing layer (3) is provided on one of the front and back surfaces of the base film (1), and the adhesive layer (4) is provided on the other front and back surfaces of the base film (1). It may be an asymmetric configuration including a base film (2) through the intermediary.

Further, the other side of the front and back of the base film (2), or the front and back of the present particle-containing layer (3), or between the base film (1) and the base film (2), or A layer having various functions (also referred to as a “functional layer”) may be provided between the material film (1) and the present particle-containing layer (3), or at two or more of these layers. .
Examples of the functional layer include layers such as an anchor coat layer, an inorganic-containing layer, an easy-adhesion layer, and an intermediate buffer layer. Each functional layer will be described later.

<<< optical characteristics of the present protective film >>>
In the present protective film, the difference between the reflectance R2 of the film surface opposite to the particle-containing layer and the reflectance R1 of the particle-containing layer-side surface is greater than 4% from the viewpoint of suppressing Newton's ring phenomenon and improving brightness. More preferably, it is more preferably more than 5%, especially more than 6%, and especially more than 10%. The upper limit is not particularly limited, but can be considered to be about 20% in consideration of the light control effect.

  The present protective film is an optical protective film provided with a particle-containing layer on the front and back surfaces of the base film (1) as described above, and has a reflectance R2 of a film surface opposite to the particle-containing layer, As long as the optical layer has an optical property that the difference from the reflectance R1 of the surface of the containing layer is larger than 4%, the particle containing layer is positioned closer to the light source than the base film as shown in FIGS. Along with disposing the present protective film so that the phosphor screen containing the phosphor is disposed on the display screen side of the present protective film, in other words, on the side opposite to the light source, the present protective film is formed by the particle-containing layer. The generation of the Newton ring phenomenon can be suppressed, and the light from the light source can be suitably transmitted and supplied to the phosphor sheet. Of the light excited by the phosphor and emitted in the 360 ° direction, , Motoho Since the light incident on the film side can be reflected to the phosphor sheet side, it is possible to increase the brightness of the display screen to increase the luminous efficiency of the phosphor.

From the viewpoint of suppressing the occurrence of the Newton ring phenomenon and improving the luminance, the reflectance R1 is preferably smaller than 14%, more preferably smaller than 10%, and particularly preferably smaller than 6%. The lower limit is not particularly limited, but can be considered to be about 5% in consideration of the light control effect.
On the other hand, from the viewpoint of suppressing the occurrence of the Newton ring phenomenon and improving the luminance, the reflectance R2 is preferably greater than 14%, more preferably greater than 16%, and particularly preferably greater than 18%. The upper limit is not particularly limited, but can be considered to be about 26% in consideration of the light control effect.

From the viewpoint of suppressing Newton's ring phenomenon occurrence and improving brightness, the present protective film has a light transmittance T1 measured when light is irradiated from the particle-containing layer side, and is irradiated with light from the side opposite to the particle-containing layer. It is preferable to have an optical property of being larger than the light transmittance T2 measured at that time.
At this time, the difference between the light transmittance T1 and the light transmittance T2 is preferably larger than 4%, particularly larger than 5%, and particularly larger than 6%, from the viewpoint of suppressing the occurrence of the Newton ring phenomenon and improving the brightness. More preferably, it is more than 10%. The upper limit is not particularly limited, but can be considered to be about 20% in consideration of the light control effect.

Above all, the light transmittance T1 is preferably larger than 87%, more preferably larger than 88%, more preferably larger than 89%. The upper limit is not particularly limited, but can be considered to be about 90% in consideration of the light control effect.
On the other hand, the light transmittance T2 is preferably less than 85%, more preferably less than 80%, more preferably less than 76%. The lower limit is not particularly limited, but can be considered to be about 74% in consideration of the light control effect.

  Furthermore, the total value of the light transmittance T1 and the reflectance R1 is greater than 97%, especially greater than 98%, and the total value of the light transmittance T2 and the reflectance R2 is greater than 97%, especially 98% % Is preferred. It is preferable that the total value be greater than 97%, since light from the light source can be efficiently supplied to the display screen.

Further, the film haze value of the present protective film is preferably larger than 40% from the viewpoint of suppressing the occurrence of Newton's ring phenomenon, more preferably larger than 50%, particularly larger than 60%, and more preferably larger than 70%. preferable.
Although the haze value of the film used for optical applications may not be considered by technical common sense to be greater than 40%, the haze value of the protective film has the special optical characteristics as described above. Is larger than 40%, it can be suitably used for optical applications.

<< water vapor permeability characteristics of the present protective film >>
The present protective film preferably has a water vapor transmission rate (WvTR) of less than 1 g / m ² / day.
Since an optical member, for example, a sheet containing a phosphor such as a quantum dot may be deteriorated by water vapor, from the viewpoint of protecting the optical member, the present protective film has a water vapor transmission rate (WvTR) of 1 g / m ² / m. It is preferably smaller than day, particularly preferably smaller than 0.5 g / m ² / day, more preferably smaller than 0.1 g / m ² / day.
Here, the above-mentioned water vapor transmission rate (WvTR) can be measured by the measuring method shown in Examples described later.
In the present protective film, as a means for making the water vapor transmission rate (WvTR) smaller than 1 g / m ² / day, for example, a method of laminating an inorganic material-containing layer described later can be mentioned. However, it is not limited to this method.

<<< Particle-containing layer >>
The present particle-containing layer preferably contains a binder resin and particles having an average particle size of 3 μm to 10 μm in order to impart the above-mentioned optical properties to the present protective film.
If the average particle diameter of the particles contained in the present particle-containing layer is 3 μm or more, it is effective to impart the above optical characteristics, and if it is 10 μm or less, the surface roughness of the film does not become too coarse, In a post-process, it is possible to suppress the occurrence of problems such as falling off of particles.
From this viewpoint, the average particle size of the particles contained in the present particle-containing layer is preferably 3 μm to 10 μm, more preferably 3 μm or more, or 8 μm or less, among which 3 μm or more, or 6 μm or less, among which 3 μm or more, or 5 μm or less. Is more preferred.
The average particle diameter of the particles in the present particle-containing layer is determined by arbitrarily selecting 10 or more particles present in the present particle-containing layer by a scanning electron microscope (SEM), and measuring the diameter of each particle. It can be obtained as an average value. At that time, in the case of non-spherical particles, the average value of the longest diameter and the shortest diameter ((minor diameter + long diameter) / 2) can be measured as the diameter of each particle.

In order to impart the above-mentioned optical properties to the present protective film, the present particle-containing layer may be present in combination with large particles having a particle size of 3 μm to 10 μm and small particles having a particle size of 1 μm to 5 μm. More preferred.
At this time, the particle size of each particle can be determined by a scanning electron microscope (SEM). In the case of a non-spherical particle, the average value of the longest diameter and the shortest diameter can be measured as the diameter of each particle.
The size of the large particles is more preferably 5 μm or more and 10 μm or less, and more preferably 5 μm or more or 8 μm or less.
On the other hand, the particle size of the small particles is more preferably 2 μm or more or 5 μm or less, and particularly preferably 2 μm or more or 4 μm or less.
In the present particle-containing layer, particles having different sizes may be present in addition to the particles having the large particle size and the particles having the small particle size.

  When the present particle-containing layer contains large particles having a particle size of 3 μm to 10 μm and small particles having a particle size of 1 μm to 5 μm, and further contains particles having other sizes as necessary. Large particles having a particle size of 3 μm to 10 μm preferably occupy 40 to 80% by mass of the particles contained in the particle-containing layer, and more preferably 50% by mass or more or 80% by mass or less, among which 50% by mass or more Alternatively, the content is more preferably 70% by mass or less.

The type of particles contained in the present particle-containing layer is not particularly limited. For example, silica, clay, talc, calcium carbonate, calcium sulfate, barium sulfate, aluminum silicate, titanium oxide, synthetic zeolite, alumina, may be inorganic particles such as smectite, styrene resin, urethane resin, benzoguanamine resin, Organic fine particles such as silicone resin and acrylic resin may be used, or two or more of these may be used in combination.
Above all, it is preferable to use acrylic beads composed of an acrylic crosslinked resin from the viewpoints of the transparency and scratch resistance of the particles.

  The shape of the particles is not particularly limited. For example, the shape may be spherical, massive, rod-like, flat, or the like. These particles may be used in combination of two or more as necessary.

  On the other hand, as the binder constituting the present particle-containing layer, for example, a polymer comprising a polyester resin, an acrylic resin, an acrylic urethane resin, a polyester acrylate resin, a polyurethane acrylate resin, an epoxy acrylate resin, and a urethane resin Resin can be used.

The particle content in the present particle-containing layer is preferably from 40 to 300 parts by mass based on 100 parts by mass of the binder resin. Satisfying the above range is preferable because control of transmittance and reflectance by light scattering property of the film, that is, compatibility of so-called light control and transparency can be achieved.
From such a viewpoint, the content of the particles in the particle-containing layer is preferably 40 to 300 parts by mass with respect to 100 parts by mass of the binder resin, more preferably 50 parts by mass or more or 200 parts by mass or less, and among them, 60 parts by mass or more. Alternatively, the amount is more preferably 100 parts by mass or less.

  The ratio of the average particle diameter of the particles in the present particle-containing layer to the maximum thickness of the present particle-containing layer is preferably 1/6 to 1/2, and more preferably 1/5 or more or 1/2 or less. Among them, it is more preferable that the ratio is not less than 1/4 or not more than 1/2.

<<< base film >>>
The base film (the base film (1) and the base film (2) also belong to the “base film”) has transparency and has sufficient and sufficient rigidity as a protective film. The material and configuration are not limited as long as it is a film.

The present base film may have a single-layer structure or a multilayer structure.
When the present base film has a multi-layer structure, it may have a multi-layer structure of four or more layers besides the two-layer and three-layer structures without departing from the gist of the present invention.

Regardless of whether the base film has a single-layer configuration or a multilayer configuration, the main component resin of each layer is preferably polyester.
At this time, the “main component resin” means a resin having the highest content ratio among the resins constituting the present base film, and is, for example, 50% by mass or more, particularly 70% by mass, of the resins constituting the present base film. %, Especially 80% by mass or more (including 100% by mass).
Each layer of the present base film may contain a resin other than polyester or a component other than resin as long as it contains polyester as a main component resin.

The polyester may be a homopolyester or a copolyester.
In the case of a homopolyester, those obtained by polycondensing an aromatic dicarboxylic acid and an aliphatic glycol are preferred.
Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid.
Examples of the aliphatic glycol include ethylene glycol, diethylene glycol, 1,4-cyclohexanedimethanol, and the like.
Typical polyesters include polyethylene terephthalate and the like.

  On the other hand, examples of the dicarboxylic acid component of the copolymerized polyester include one or more of isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, and sebacic acid. One or more of glycol, diethylene glycol, propylene glycol, butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol and the like can be mentioned.

  Specific examples of polyester include, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polybutylene naphthalate (PBN), polyarylates, polyether sulfone, polycarbonate, polyether ketone, Examples include polysulfone, polyphenylene sulfide, polyester-based liquid crystal polymer, triacetyl cellulose, cellulose derivatives, polypropylene, polyamides, polyimides, and polycycloolefins. Among them, PET and PEN are preferable from the viewpoint of handleability.

The present base film may contain particles for the purpose of roughening the film surface to impart lubricity and for the main purpose of preventing scratching in each step.
The type of the particles is not particularly limited as long as the particles can impart lubricity. For example, silica, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, inorganic particles such as titanium oxide, acrylic resin, styrene resin, urea resin, phenol resin, epoxy resin, benzoguanamine Organic particles such as resin can be used. These may be used alone or in combination of two or more of them.
Further, during the polyester production step, precipitated particles in which a part of a metal compound such as a catalyst is precipitated and finely dispersed can be used.
The shape of the particles is not particularly limited. For example, the shape may be any of a sphere, a lump, a rod, a flat shape, and the like.
The hardness, specific gravity, color and the like of the particles are not particularly limited. These series of particles may be used in combination of two or more as necessary.

  The average particle diameter of the particles is preferably 5 μm or less, more preferably 0.01 μm or more and 3 μm or less, more preferably 0.5 μm or more and 2.5 μm or less. If it exceeds 5 μm, the surface roughness of the present base film may be too coarse, and a problem may occur when various surface functional layers are formed in a subsequent step.

  The particle content is preferably 5% by mass or less of the present substrate film, more preferably 0.0003% by mass or 3% by mass or less, and particularly preferably 0.01% by mass or more or 2% by mass or less. More preferred. It is preferable that the particle content be in such a range, since it is possible to achieve both the slipperiness and the transparency of the film.

  The method for adding particles to the substrate film is not particularly limited, and a conventionally known method can be employed. For example, it can be added at any stage of producing the polyester. Preferably, it is added after the completion of the esterification or transesterification reaction.

  If necessary, conventionally known antioxidants, antistatic agents, heat stabilizers, lubricants, dyes, pigments, ultraviolet absorbers and the like can be added to the present base film.

  The thickness of the present base film is not particularly limited as long as it can be formed into a film, and is preferably 9 μm to 100 μm, and more preferably 12 μm or more or 75 μm or less, among which 15 μm or more or 60 μm or less. More preferably, there is.

The present base film can be formed, for example, by forming a resin composition into a film shape by a melt casting method or a solution casting method. In the case of a multilayer structure, it may be co-extruded.
Further, it may be uniaxially stretched or biaxially stretched, and a biaxially stretched film is preferred from the viewpoint of rigidity.

<< adhesive layer >>
As described above, the present base film includes the present particle-containing layer (3) on the front and back surfaces of the base film (1) as shown in FIG. Alternatively, an asymmetric configuration including a base film (2) via an adhesive layer (4) may be employed.
In this case, the adhesive layer (4) may be appropriately selected from known adhesives and used. Above all, a known adhesive capable of adhering the polyester films to each other and ensuring transparency can be appropriately selected and used. For example, an adhesive comprising one or a combination of two or more of polyester, polyvinyl alcohol, acrylic resin, urethane resin, polyalkylene glycol, polyalkyleneimine, methylcellulose, and hydroxycellulose can be used.

<< functional layer >>
As described above, the other side of the front and back surfaces of the base film (2), or the front and back surfaces of the present particle-containing layer (3), or between the base film (1) and the base film (2), Alternatively, between the base film (1) and the present particle-containing layer (3), or in two or more of these layers, a layer having various functions, that is, a functional layer may be provided as necessary. Can be.
Examples of the functional layer include layers such as an anchor coat layer, an inorganic-containing layer, an easy-adhesion layer, and an intermediate buffer layer described below. However, it is not limited to these.

<Anchor coat layer>
The anchor coat layer includes a base film (1) and a base film (2), a base film (1) and a present particle-containing layer (3), a base film (1) and each functional layer, or a base film. This is a layer for improving the adhesiveness between (2) and each functional layer, and can be provided as needed.

The anchor coat layer can be formed from an anchor coat agent.
Examples of the anchor coating agent include a solvent-based or aqueous polyester, a urethane resin, an acrylic resin, a vinyl alcohol resin, an ethylene vinyl alcohol resin, a vinyl-modified resin, an oxazoline group-containing resin, a carbodiimide group-containing resin, an epoxy group-containing resin, and an isocyanate group. Resins, alkoxyl group-containing resins, modified styrene resins, modified silicone resins, and the like. These can be used alone or in combination of two or more. Among them, from the viewpoint of adhesion and hot water resistance, at least one selected from polyester, urethane resin, acrylic resin, oxazoline group-containing resin, carbodiimide group-containing resin, epoxy group-containing resin, isocyanate-containing resin and a copolymer thereof. It is preferable to use alone or in combination of two or more, and among them, one or more of polyester, urethane resin, acrylic resin, and oxazoline group-containing resin, carbodiimide group-containing resin, epoxy group-containing resin, and isocyanate group-containing resin It is preferable to use at least one selected one alone or in combination of two or more.

When the thickness of the anchor coat layer is 5 μm or less, the sliding property is good, there is almost no peeling from the base film due to the internal stress of the anchor coat layer itself, and the thickness is 0.005 μm or more. It is preferable to maintain a uniform thickness.
From this viewpoint, the thickness of the anchor coat layer is preferably 0.005 to 5 μm, more preferably 0.01 μm or more and 1 μm or less, and more preferably 0.02 μm or more or 0.5 μm or less.

<Inorganic substance containing layer>
The inorganic-containing layer is a layer mainly for suppressing gas permeation, and can be provided as necessary.

The inorganic material-containing layer is a layer containing an inorganic material, particularly an inorganic oxide as a main component, and is excellent not only in gas barrier properties, particularly in water vapor barrier properties, but also in easy film formation, and furthermore, adhesion to other layers. Is also excellent.
The main component means that the inorganic material accounts for 50% by mass or more, particularly 70% by mass or more, particularly 80% by mass or more, especially 90% by mass or more of the inorganic material-containing layer.

  The inorganic material-containing layer is at least one selected from the group consisting of silicon oxide, silicon nitride, silicon oxynitride, silicon oxycarbide, silicon oxycarbonitride, aluminum oxide, aluminum nitride, aluminum oxynitride, and aluminum oxycarbide. What contains the inorganic compound of is preferable.

  As described below, the inorganic-containing layer may be formed by, for example, a physical vapor deposition (PVD) method, a chemical vapor deposition (CVD) method, or a method in which inorganic particles are dispersed in an organic polymer and applied. Can be formed.

(PVD inorganic material containing layer)
The inorganic material-containing layer preferably includes at least one PVD inorganic material-containing layer formed by a PVD method. Thereby, high gas barrier properties can be exhibited.

The PVD inorganic material-containing layer is preferably a layer composed of a silicon oxide represented by, for example, SiOx (1.0 <X ≦ 2.0).
The PVD inorganic-containing layer is composed of a silicon oxide represented by SiOx (1.0 <X≤2.0). If the value of X (lower limit) is smaller, the gas permeability is smaller. In some cases, the silicon oxide film itself becomes yellowish and the transparency is reduced. The above composition can be confirmed by XPS (X-ray photoelectron spectroscopy) analysis or the like.

The preferable pressure at the time of forming the PVD inorganic material-containing layer is preferably 1 × 10 ⁻⁷ to 1 Pa, and more preferably 1 × 10 ⁻⁶ or more, from the viewpoints of gas barrier properties, vacuum evacuation ability, and the degree of oxidation of the SiOx layer to be formed. or 1 × 10 ^-1 Pa or less, and more preferably 1 × 10 ^-4 or more, or 1 × 10 ^-2 Pa or less therein. The partial pressure during the introduction of oxygen is in the range of 10 to 90%, more preferably 20 to 80%, based on the total pressure.

  The inorganic material-containing layer may have a single-layer structure composed of the above-mentioned PVD inorganic material-containing layer, or a chemical vapor (for example, JP-A-2013-226829) may be formed on the PVD inorganic material-containing layer in order to ensure higher gas barrier properties. And the like, a multilayer structure (two or more layers) in which a CVD inorganic material-containing layer formed by a vapor deposition method or a PVD inorganic material-containing layer having the same or different composition is formed.

  A configuration in which a PVD inorganic material-containing layer and a CVD inorganic material-containing layer are alternately formed (for example, a three-layer structure of a PVD inorganic material-containing layer, a CVD inorganic material-containing layer, and a PVD inorganic material-containing layer) may be used. In particular, by forming a CVD inorganic material-containing layer on a PVD inorganic material-containing layer, defects or the like generated in the PVD inorganic material-containing layer are monitored, and gas barrier properties and adhesion between layers tend to be improved.

(CVD inorganic-containing layer)
The CVD inorganic-containing layer contains carbon, and the carbon content is 20 at. %, Preferably at least 10 at. %, More preferably 5 at. % Is most preferred. When the carbon content satisfies the above range, the surface energy of the inorganic material-containing layer is increased, and the adhesion between the inorganic material-containing layers is improved, so that the bending resistance and peeling resistance of the barrier film are improved. I do.
The carbon content of the CVD inorganic-containing layer is 0.5 at. % Or more, preferably 1 at. % Or more, more preferably 2 at. % Or more is good. By containing a trace amount of carbon in the intermediate layer containing a CVD inorganic substance, stress can be alleviated efficiently and the curl of the barrier film itself can be reduced.
Note that “at.%” Indicates the atomic composition percentage (atomic%). The composition can be confirmed by XPS analysis or the like.

The formation of the CVD inorganic-containing layer is preferably performed under a reduced pressure environment of 10 Pa or less and at a transport speed of the present base film, particularly the present base film provided with the anchor coat layer, of 100 m / min or more. The pressure at the time of forming a thin film by chemical vapor deposition (CVD) is preferably performed under reduced pressure in order to form a dense thin film, and is preferably 10 Pa or less from the viewpoint of the film forming rate and barrier properties. More preferably, it is 1 × 10 ⁻² or more or 10 Pa or less, and more preferably 1 × 10 ⁻¹ or more or 1 Pa or less.

  If necessary, the CVD inorganic-containing layer may be subjected to a cross-linking treatment by electron beam irradiation in order to improve water resistance and durability.

The CVD inorganic-containing layer is preferably composed of a thin film containing at least one selected from metals, metal oxides and metal nitrides. More preferably, metals such as silicon and aluminum are preferable in terms of gas barrier properties and adhesion. In addition, as the metal oxide or metal nitride, it is preferable to use an oxide, a nitride of the metal, or a mixture thereof from the viewpoint of gas barrier properties and adhesion.
As the CVD inorganic-containing layer, a layer composed of at least one selected from silicon oxide, silicon oxycarbide, silicon oxynitride, silicon oxycarbonitride, silicon nitride, and aluminum oxide is more preferable. Further, as the metal oxide or metal nitride, those obtained by plasma-decomposing an organic compound are preferable.

  As a raw material for forming a CVD inorganic material-containing layer such as a silicon oxide film, any compound such as a silicon compound can be used in a gas, liquid or solid state at normal temperature and normal pressure. In the case of gas, it can be directly introduced into the discharge space. In the case of a liquid or solid, it is used after being vaporized by means such as heating, bubbling, decompression, and ultrasonic irradiation. Further, the solvent may be used after dilution, and as the solvent, an organic solvent such as methanol, ethanol, n-hexane or the like and a mixed solvent thereof can be used.

  Examples of the silicon compound include silane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetra-t-butoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, and diethyldimethoxysilane. Silane, diphenyldimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, phenyltriethoxysilane, (3,3,3-trifluoropropyl) trimethoxysilane, hexamethyldisiloxane, bis (dimethylamino) dimethylsilane, bis (Dimethylamino) methylvinylsilane, bis (ethylamino) dimethylsilane, N, O-bis (trimethylsilyl) acetamide, bis (trimethylsilyl) carbodiimide, diethylamido Trimethylsilane, dimethylaminodimethylsilane, hexamethyldisilazane, hexamethylcyclotrisilazane, heptamethyldisilazane, nonamethyltrisilazane, octamethylcyclotetrasilazane, tetrakisdimethylaminosilane, tetraisocyanatosilane, tetramethyldisilazane, tris (Dimethylamino) silane, triethoxyfluorosilane, allyldimethylsilane, allyltrimethylsilane, benzyltrimethylsilane, bis (trimethylsilyl) acetylene, 1,4-bistrimethylsilyl-1,3-butadiyne, di-t-butylsilane, 1, 3-disilabutane, bis (trimethylsilyl) methane, cyclopentadienyltrimethylsilane, phenyldimethylsilane, phenyltrimethylsilane, propargyl Limethylsilane, tetramethylsilane, trimethylsilylacetylene, 1- (trimethylsilyl) -1-propyne, tris (trimethylsilyl) methane, tris (trimethylsilyl) silane, vinyltrimethylsilane, hexamethyldisilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane , Hexamethyldisiloxane, hexamethylcyclotetrasiloxane, M silicate 51 and the like.

The thickness of the inorganic material-containing layer (when the inorganic material-containing layer has a multilayer structure, the total thickness thereof) is preferably from 0.1 nm to 500 nm, and more preferably 1 nm or more or 300 nm or less, among which 5 nm or more or 100 nm or less. Is more preferred.
When the thickness of the inorganic material-containing layer is within such a range, it is possible to secure desired gas barrier properties.

(Layer composition of inorganic-containing layer)
The inorganic material-containing layer is preferably composed of two or more layers by laminating a flexible layer on the inorganic material-containing layer. That is, a coarse projection of the base film is generated as a starting point, or when the inorganic-containing layer is formed by heating and vapor deposition, the raw material may fly and adhere to the inorganic-containing layer. In some cases, a small defect called a pinhole may occur, and the gas barrier property may be reduced by the gas passing through the void due to this defect.Therefore, a layer made of a flexible material is added to the inorganic-containing layer. It is preferable to stack two or more layers to further enhance the gas barrier properties.

At this time, the flexible layer is made of a flexible composition that easily fills the voids of the inorganic material-containing layer, for example, an organic material such as a polyester resin, an acrylic resin, a urethane resin, or polyvinyl alcohol (PVA), or an inorganic or organic material. It is preferably a layer containing a filler as a main component.
The main component means that the main component accounts for 50% by mass or more, especially 70% by mass or more, especially 80% by mass or more, especially 90% by mass or more of the flexible layer.

<Easy adhesion layer>
The easy-adhesion layer includes the base film (1) and the base film (2), the base film (1) and the present particle-containing layer (3), the base film (1) and each functional layer, or the base film. This is a layer for enhancing the adhesion between (2) and each functional layer, or between the base film (2) and various optical members, for example, a phosphor-containing sheet, and can be provided as necessary.

  From the viewpoint of improving the adhesion between the base material film (2) and the phosphor-containing sheet, particularly the quantum dot layer or the quantum dot film, the easy-adhesion layer is formed of a compound having at least a carbon-carbon double bond and urethane. It is preferable to form a layer containing any of the resins.

(Compound having a carbon-carbon double bond)
Examples of the compound having a carbon-carbon double bond include compounds having a monofunctional (meth) acrylate group, a difunctional (meth) acrylate group, a polyfunctional (meth) acrylate group, a vinyl group, an allyl group, or the like. it can.
The expression “(meth) acrylate compound” indicates “acrylate compound and methacrylate compound”.

  The monofunctional (meth) acrylate is not particularly limited. For example, alkyl (such as methyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, and isobornyl (meth) acrylate Hydroxyalkyl (meth) acrylates such as meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate; methoxyethyl (meth) acrylate; ethoxyethyl (meth) acrylate; A) alkoxyalkyl (meth) acrylates such as acrylate and ethoxypropyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) Aromatic (meth) acrylates such as acrylates, diaminoethyl (meth) acrylates, amino group-containing (meth) acrylates such as diethylaminoethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, Examples include ethylene oxide-modified (meth) acrylate such as phenylphenol ethylene oxide-modified (meth) acrylate, glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, and (meth) acrylic acid.

  The bifunctional (meth) acrylate is not particularly limited. For example, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tricyclodecanedi Alkanediol di (meth) acrylates such as methylol di (meth) acrylate, bisphenol A ethylene oxide-modified di (meth) acrylate, bisphenol F ethylene oxide-modified di (meth) acrylate such as bisphenol-modified di (meth) acrylate, polyethylene glycol di Examples thereof include (meth) acrylate, polypropylene glycol di (meth) acrylate, urethane di (meth) acrylate, and epoxy di (meth) acrylate.

  The polyfunctional (meth) acrylate is not particularly limited. For example, dipentaerythritol hexa (meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropanetetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropanetri (meth) acrylate, modified with tetramethylolmethane ethylene oxide Isocyanuric acid-modified tri (meth) acrylates such as tetra (meth) acrylate, isocyanuric acid ethylene oxide-modified tri (meth) acrylate, ε-caprolactone-modified tris (acryloxyethyl) isocyanurate, and pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer , Pentaerythritol triacrylate toluene diisocyanate urethane prepolymer, And pentaerythritol pentaacrylate hexamethylene diisocyanate urethane acrylates such as urethane prepolymer.

These compounds having a monofunctional (meth) acrylate group, compounds having a bifunctional (meth) acrylate group, compounds having a polyfunctional (meth) acrylate group, compounds having a vinyl group, and compounds having a compound having an allyl group are: They may be used alone or in combination of two or more.
From the viewpoint of improving adhesion, among these (meth) acrylate compounds, bifunctional (meth) acrylates and polyfunctional (meth) acrylates are preferable, and among them, polyfunctional (meth) acrylate is particularly preferable.

  When a (meth) acrylate compound is used, the ratio of the carbon-carbon double bond to the (meth) acrylate compound is preferably 3% by weight or more, more preferably 3% by weight, in consideration of the adhesion to the quantum dot layer. 5% by weight or more. The upper limit is usually 40% by weight.

(Urethane resin)
The urethane resin may be a polymer compound having a urethane bond in the molecule, and may be a polymer compound obtained by a reaction between a polyol and an isocyanate.
Examples of the polyol include polycarbonate polyols, polyester polyols, polyether polyols, polyolefin polyols, acrylic polyols, and the like. These compounds may be used alone or in combination. From the viewpoint of improving adhesion, polycarbonate polyols or polyester polyols are preferred, and polycarbonate polyols are more preferred.

Examples of the polycarbonate polyols constituting the urethane resin include those obtained by a dealcoholation reaction from a polyhydric alcohol and a carbonate compound.
At this time, polyhydric alcohols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, trimethylolpropane, 1,2-butanediol, 1,3-butanediol, 1,4-butane Diol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonane Examples thereof include diol, 1,10-decanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, and 3,3-dimethylolheptane.
Examples of the carbonate compound include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and the like. Polycarbonate polyols obtained from these reactions include, for example, poly (1,6-hexylene) carbonate, poly ( 3-methyl-1,5-pentylene) carbonate and the like.

  Examples of the polyester polyols constituting the urethane resin include polycarboxylic acids (malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid, etc.). ) Or their anhydrides and polyhydric alcohols (ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, 1,3-butanediol, 1,4-butanediol, , 3-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-methyl- 2,4-pentanediol, 2 Methyl-2-propyl-1,3-propanediol, 1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2,5- Dimethyl-2,5-hexanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-butyl-2-hexyl- 1,3-propanediol, cyclohexanediol, bishydroxymethylcyclohexane, dimethanolbenzene, bishydroxyethoxybenzene, alkyl dialkanolamine, lactone diol, etc.), and a derivative unit of a lactone compound such as polycaprolactone. And the like.

  Examples of the polyether polyols constituting the urethane resin include polyethylene glycol, polypropylene glycol, polyethylene propylene glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol, and the like.

  Examples of the polyisocyanate constituting the urethane resin include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, and tolidine diisocyanate; α, α, α ′, α′-tetra Aliphatic diisocyanates having an aromatic ring such as methylxylylene diisocyanate, methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, aliphatic diisocyanates such as hexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, methylene bis (4 -Cyclohexyl Isocyanate), dicyclohexylmethane diisocyanate, can be mentioned alicyclic diisocyanates such as isopropylidene dicyclohexyl diisocyanate. These may be used alone or in combination of two or more. These polyisocyanate compounds may be a dimer, a trimer represented by an isocyanuric ring, or a polymer thereof or more. Among the above isocyanates, an aliphatic isocyanate or an alicyclic isocyanate is more preferable than an aromatic isocyanate from the viewpoint of improving adhesion to an active energy ray-curable paint and preventing yellowing due to ultraviolet rays.

When synthesizing a urethane resin, a chain extender may be used. The chain extender is not particularly limited as long as it has two or more active groups that react with an isocyanate group. Alternatively, a chain extender having two amino groups can be mainly used.
Examples of the chain extender having two hydroxyl groups include aliphatic glycols such as ethylene glycol, propylene glycol, butanediol, and pentanediol, aromatic glycols such as xylylene glycol and bishydroxyethoxybenzene, neopentyl glycol, and neopentyl glycol. Glycols such as ester glycols such as hydroxypivalate can be mentioned. Examples of the chain extender having two amino groups include, for example, aromatic diamines such as tolylenediamine, xylylenediamine, diphenylmethanediamine, ethylenediamine, propylenediamine, hexanediamine, and 2,2-dimethyl-1,3- Propanediamine, 2-methyl-1,5-pentanediamine, trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10- Aliphatic diamines such as decanediamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, isoprovilitincyclohexyl-4,4′-diamine, 1,4-diaminocyclohexane, , 3-bisaminomethylcyclohexane, Alicyclic diamines such as isophorone diamine can be exemplified.

The urethane resin may be a solvent-based medium or water-based medium.
In the case of an aqueous urethane resin, in order to disperse or dissolve the urethane resin in water, there are a forced emulsification type using an emulsifier, a self-emulsification type in which a hydrophilic group is introduced into the urethane resin, and a water-soluble type. In particular, a self-emulsifying type in which an ionic group is introduced into the skeleton of the urethane resin to form an ionomer is preferable because it has excellent storage stability of the liquid and excellent water resistance, transparency and adhesion of the obtained coating layer. Examples of the ionic group to be introduced include various groups such as a carboxyl group, sulfonic acid, phosphoric acid, phosphonic acid, and a quaternary ammonium salt. Among them, a carboxyl group is preferable.
As a method for introducing a carboxyl group into the urethane resin, various methods can be adopted in each stage of the polymerization reaction. For example, a method using a resin having a carboxyl group as a copolymerization component at the time of prepolymer synthesis, or a method using a component having a carboxyl group as one component such as a polyol, a polyisocyanate, or a chain extender can be adopted. In particular, a method in which a desired amount of a carboxyl group is introduced by using a carboxyl group-containing diol depending on the charged amount of this component is preferable. For example, copolymerizing dimethylolpropionic acid, dimethylolbutanoic acid, bis- (2-hydroxyethyl) propionic acid, bis- (2-hydroxyethyl) butanoic acid, etc. with a diol used for the polymerization of urethane resin. Can be. The carboxyl group is preferably in the form of a salt neutralized with ammonia, an amine, an alkali metal, an inorganic alkali or the like. Particularly preferred are ammonia, trimethylamine and triethylamine. In such a urethane resin, a carboxyl group from which a neutralizing agent has been removed in a drying step of a coating solution can be used as a crosslinking reaction point by another crosslinking agent. Thereby, the stability in a coating liquid state is excellent, and the durability, water resistance, blocking resistance, and the like of the obtained easily adhesive layer can be further improved.

(Binder polymer)
The easy-adhesion layer preferably contains a binder polymer in addition to the urethane resin or the compound having a carbon-carbon double bond, from the viewpoint of improving the appearance of application, transparency, and adhesion.

  A binder polymer is a polymer having a high number average molecular weight (Mn) of 1000 or more measured by gel permeation chromatography (GPC) according to a flow chart for safety evaluation of polymer compounds (sponsored by the Chemical Substances Council in November 1985). It is a polymer that is a molecular compound and has a film-forming property, and as a necessary condition, a polymer having a number average molecular weight (Mn) of 1000 or more and a polymer having a film-forming property.

  Specific examples of the binder polymer include, for example, polyester resin, polyvinyl (polyvinyl alcohol, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer), polyalkylene glycol, polyalkyleneimine, methylcellulose, hydroxycellulose, starch, and the like. These may be used alone, or two or more of them may be used in combination.

  The polyester resin as the binder polymer may be a resin composed of the following polyvalent carboxylic acid and polyvalent hydroxy compound as main components.

  Examples of the polycarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, phthalic acid, 4,4′-diphenyldicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, and 2,6-naphthalene Dicarnonic acid, 2,7-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2-potassium sulfoterephthalic acid, 5-sodium sulfoisophthalic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, glutar Acid, succinic acid, trimellitic acid, trimesic acid, pyromellitic acid, trimellitic anhydride, phthalic anhydride, p-hydroxybenzoic acid, monopotassium trimellitic acid and their ester-forming derivatives can be used. .

  Examples of the polyhydric hydroxy compound include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and Methyl-1,5-pentaneddiol, neopentyl glycol, 1,4-cyclohexanedimethanol, p-xylylene glycol, ethylene glycol-modified bisphenol A, diethylene glycol-modified bisphenol A, diethylene glycol, triethylene glycol, polyethylene Glycol, polypropylene glycol, polytetramethylene glycol, polytetramethylene oxide glycol, dimethylolpropionic acid, glycerin, trimethylolpropane, sodium dimethylolethylsulfonate, dimethylo Or the like can be used potassium Rupuropion acid. One or more of these polycarboxylic acids and polyhydroxy compounds may be appropriately selected, and a polyester resin may be synthesized by a conventional polycondensation reaction.

  The polyvinyl alcohol as the binder polymer may be any compound having a polyvinyl alcohol moiety. For example, conventionally known polyvinyl alcohols may be used, including modified compounds in which polyvinyl alcohol is partially acetalized or butyralized.

The degree of polymerization of polyvinyl alcohol is not particularly limited, and is preferably 100 or more, more preferably 300 or more, or 40,000 or less, more preferably 500 or more, or 10,000 or less. By satisfying this range, the water resistance of the coating layer can be secured.
The saponification degree of the polyvinyl alcohol is not particularly limited, and is preferably 70 mol% or more, more preferably 80 mol% or more or 99.9 mol% or less, among which 86 mol% or more or 97 mol% or less, among which More preferably, it is at most 95 mol%.

From the viewpoint of obtaining good adhesion to the quantum dot layer, the content of the binder polymer in the easy-adhesion layer is preferably 30% by weight or more, more preferably 40% by weight or more, and especially 50% by weight or more. Is more preferred.
On the other hand, from the viewpoint of obtaining good coating strength, the content of the binder polymer in the easy-adhesion layer is preferably 90% by weight or less, more preferably 80% by weight or less, and particularly preferably 75% by weight or less. Is more preferred.

(Crosslinking agent)
The easy-adhesion layer can further include a crosslinking agent to increase the degree of cross-linking of the easy-adhesion layer, thereby improving its adhesiveness and durability.

  As the crosslinking agent, it is preferable to use an oxazoline compound, an isocyanate compound, an epoxy compound, a melamine compound, and a carbodiimide compound. Among them, it is more preferable to use at least one of an oxazoline compound and an isocyanate compound from the viewpoint of improving adhesion.

The oxazoline compound used for the cross-linking agent is a compound having an oxazoline group in the molecule, particularly preferably a polymer containing an oxazoline group, and can be prepared by polymerization with an addition-polymerizable oxazoline group-containing monomer alone or another monomer. . The addition-polymerizable oxazoline group-containing monomer is 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, Examples thereof include 2-isopropenyl-4-methyl-2-oxazoline and 2-isopropenyl-5-ethyl-2-oxazoline. One or a mixture of two or more of these can be used. Among them, 2-isopropenyl-2-oxazoline is easily available industrially and is preferable. The other monomer is not limited as long as it is a monomer copolymerizable with an addition-polymerizable oxazoline group-containing monomer, and examples thereof include an alkyl (meth) acrylate (as the alkyl group, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, (meth) acrylic esters such as n-butyl group, isobutyl group, t-butyl group, 2-ethylhexyl group and cyclohexyl group); acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and styrene Unsaturated carboxylic acids such as sulfonic acid and salts thereof (sodium salt, potassium salt, ammonium salt, tertiary amine salt, etc.); unsaturated nitriles such as acrylonitrile, methacrylonitrile; (meth) acrylamide, N-alkyl ( (Meth) acrylamide, N, N-dialkyl (meth) acrylamide, Examples of the alkyl group include unsaturated amides such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, 2-ethylhexyl group, cyclohexyl group, etc .; vinyl acetate , Vinyl esters such as vinyl propionate; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; α-olefins such as ethylene and propylene; halogen-containing α, β-unsaturated monomers such as vinyl chloride and vinylidene chloride; Examples thereof include α, β-unsaturated aromatic monomers such as α-methylstyrene, and one or more of these monomers can be used.
From the viewpoint of improving the adhesion, the amount of the oxazoline group of the oxazoline compound is preferably 0.5 to 10 mmol / g, more preferably 1 mmol / g or more or 9 mmol / g or less, and among them, 3 mmol / g or more or 8 mmol / g or less. And more preferably, 4 mmol / g or more or 6 mmol / g or less.

  The isocyanate compound used for the crosslinking agent is a compound having an isocyanate derivative structure represented by isocyanate or blocked isocyanate. Examples of the isocyanate include aromatic isocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, and naphthalene diisocyanate, and aromatic rings such as α, α, α ′, α′-tetramethyl xylylene diisocyanate. Aliphatic isocyanates such as aliphatic isocyanate, methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, methylene bis (4-cyclohexyl isocyanate), isopropylidene dicyclohexyl diisocyanate Ne Can be exemplified alicyclic isocyanates such bets like. Further, polymers and derivatives such as buret compounds, isocyanurate compounds, uretdione compounds, and carbodiimide modified products of these isocyanates are also included. These may be used alone or in combination of two or more. Among the above isocyanates, an aliphatic isocyanate or an alicyclic isocyanate is preferable as a countermeasure against yellowing caused by ultraviolet irradiation.

  When used in the form of a blocked isocyanate, examples of the blocking agent include bisulfites, phenolic compounds such as phenol, cresol and ethylphenol, propylene glycol monomethyl ether, ethylene glycol, benzyl alcohol, alcohols such as methanol and ethanol. Compounds, active methylene compounds such as methyl isobutanoyl acetate, dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, acetylacetone, mercaptan compounds such as butyl mercaptan, dodecyl mercaptan, ε-caprolactam, δ-valerolactam, etc. Lactam compounds, amine compounds such as diphenylaniline, aniline, ethyleneimine, acetanilide, acid amide compounds of acetic acid amide, Oxime compounds such as aldehyde, acetoaldoxime, acetone oxime, methyl ethyl ketone oxime, and cyclohexanone oxime may be mentioned, and these may be used alone or in combination of two or more.

  The isocyanate-based compound may be used alone, or may be used as a mixture or a binder with various polymers. From the viewpoint of improving the dispersibility and crosslinkability of the isocyanate compound, it is preferable to use a mixture or a binder with a polyester resin or a urethane resin.

  The epoxy compound used for the cross-linking agent is a compound having an epoxy group in the molecule, for example, condensation of epichlorohydrin with a hydroxyl group or an amino group such as ethylene glycol, polyethylene glycol, glycerin, polyglycerin, and bisphenol A. And a polyepoxy compound, a diepoxy compound, a monoepoxy compound, a glycidylamine compound and the like. Examples of the polyepoxy compound include sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, triglycidyl tris (2-hydroxyethyl) isocyanate, glycerol polyglycidyl ether, and trimethylolpropane. Examples of the polyglycidyl ether and diepoxy compound include neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, resorcin diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and propylene glycol diglycidyl ether. , Polypropylene glycol diglycidyl ether, Examples of tetramethylene glycol diglycidyl ether and monoepoxy compounds include, for example, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and glycidylamine compounds of N, N, N ′, N′-tetraglycidyl-m-xylyl. Examples thereof include diamine, 1,3-bis (N, N-diglycidylamino) cyclohexane, and the like. From the viewpoint of improving adhesion, a polyether-based epoxy compound is preferable. Further, the amount of the epoxy group is preferably a polyfunctional polyepoxy compound having three or more functional groups rather than two functional groups.

  The melamine compound used for the crosslinking agent is a compound having a melamine skeleton in the compound, for example, an alkylolated melamine derivative, partially or completely etherified by reacting an alcohol with the alkylolated melamine derivative. Compounds and mixtures thereof can be used. As the alcohol used for the etherification, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, isobutanol and the like are preferably used. The melamine compound may be any of a monomer, a dimer or a multimer, or a mixture thereof. Furthermore, a type in which urea or the like is co-condensed with a part of melamine, or a catalyst can be used in combination to improve the reactivity of the melamine compound.

The carbodiimide compound used for the cross-linking agent is a compound having a carbodiimide structure, and is a compound having one or more carbodiimide structures in the molecule. The polycarbodiimide-based compound having the above is more preferable.
This carbodiimide compound can be synthesized by a conventionally known technique, and a condensation reaction of a diisocyanate compound is generally used. The diisocyanate compound is not particularly limited, and may be any of an aromatic type and an aliphatic type. Specifically, tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, hexa Examples thereof include methylene diisocyanate, trimethylhexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, dicyclohexyl diisocyanate, and dicyclohexylmethane diisocyanate.

  The content of the carbodiimide group contained in the carbodiimide compound is preferably 100 to 1000, and more preferably 250 or more and 800 or less, in terms of carbodiimide equivalent (weight [g] of the carbodiimide compound for giving 1 mol of carbodiimide group). Among them, it is more preferably 300 or more or 700 or less. By using in the above range, the durability of the coating film is improved.

  Further, within a range that does not impair the gist of the present invention, in order to improve the water solubility and water dispersibility of the polycarbodiimide compound, adding a surfactant, polyalkylene oxide, quaternary ammonium salt of dialkylamino alcohol, A hydrophilic monomer such as a hydroxyalkyl sulfonate may be added for use.

  When such a crosslinking component is contained, a component for simultaneously promoting crosslinking, for example, a crosslinking catalyst or the like can be used in combination.

  If the easy-adhesion layer is formed in this way, it can be assumed that unreacted products of these crosslinking agents, compounds after the reaction, or a mixture thereof are present in the easy-adhesion layer.

The content of the crosslinking agent in the easy-adhesion layer is preferably 10% by weight or more, more preferably 20% by weight or more, and particularly preferably 25% by weight or more, from the viewpoint of obtaining good coating strength. preferable.
On the other hand, the content of the crosslinking agent in the easy-adhesion layer is preferably 70% by weight or less, particularly preferably 60% by weight or less, from the viewpoint of obtaining good adhesion to the phosphor sheet, particularly the quantum dot layer. Among them, the content is more preferably 50% by weight or less.

(Ingredients)
The easy-adhesion layer may contain particles for improving slipperiness and blocking.
When the easy-adhesion layer contains particles, the average particle size is preferably in the range of 1.0 μm or less, from the viewpoint of film transparency, particularly 0.5 μm or less, and in particular 0.2 μm or less. Is more preferred.
Examples of the particles contained in the easy adhesion layer include particles such as silica, alumina, kaolin, calcium carbonate, and organic particles.

The easy-adhesion layer may contain an antifoaming agent, a coating improver, a thickener, an organic lubricant, an ultraviolet absorber, an antioxidant, a foaming agent, a dye, a pigment, and the like, if necessary.
These additives may be used alone or in combination of two or more as needed.

(Formation method of easy adhesion layer)
As a method of providing the easy-adhesion layer, a conventionally known coating method such as reverse gravure coating, direct gravure coating, roll coating, die coating, bar coating, curtain coating, or the like can be used.

The easy-adhesion layer can be provided by, for example, in-line coating. However, it is not limited to this forming method.
In the case of providing by in-line coating, it is preferable to apply the above-mentioned series of compounds as an aqueous solution or an aqueous dispersion, and apply a coating solution having a solid content concentration of about 0.1 to 50% by weight on a polyester film. preferable.
In addition, a small amount of an organic solvent may be contained in the coating solution for the purpose of improving dispersibility in water, improving film forming properties, and the like as long as the gist of the present invention is not impaired. Only one type of organic solvent may be used, or two or more types may be used as appropriate.

The drying and curing conditions for forming the easy-adhesion layer are not particularly limited. For example, when the easy-adhesion layer is provided by off-line coating, usually at 80 to 200 ° C. for 3 to 40 seconds, preferably 100 to 200 ° C. The heat treatment is preferably performed at 180 ° C. for about 3 to 40 seconds.
On the other hand, when the easy-adhesion layer is provided by in-line coating, it is usually preferable to perform heat treatment at 70 to 280 ° C. for about 3 to 200 seconds.

Further, regardless of off-line coating or in-line coating, heat treatment and irradiation with active energy rays such as ultraviolet irradiation may be used in combination as needed.
The surface on which the easy-adhesion layer is to be formed may be subjected to a surface treatment such as a corona treatment or a plasma treatment in advance.

(Layer composition of easy adhesion layer)
The easy adhesion layer may be a single layer or may be composed of two or more layers.
As used herein, the “two-layer” means that the easy-adhesion layer itself may be composed of two or more layers, or may be a film configuration having an easy-adhesion layer, which may be two or more layers. It is to be interpreted.

For example, a configuration example of two or more layers including an adhesive base material layer and an adhesive layer can be given.
At this time, the adhesive layer may be as described above for the easy adhesive layer, and the thickness and the forming method may be as described above.
On the other hand, the adhesive base layer may be any layer that functions as a base material for the adhesive layer. For example, polyethylene, polypropylene, polyethylene naphthalate, polyamide, polyethylene terephthalate, polyvinyl chloride, polyvinyl alcohol, polyacrylonitrile, polyimide, polycarbonate, polyacrylate, polymethacrylate, polystyrene, ABS, cyclic olefin copolymer (COC), cycloolefin polymer And a resin layer or a resin film containing triacetyl cellulose or the like as a main component resin. These stretched films may be used to increase the strength.
The thickness of the adhesive base material layer is preferably 3 μm to 50 μm, and more preferably 4 μm or more or 30 μm or less, and particularly preferably 5 μm or more or 25 μm or less, from the viewpoint of securing the supporting properties.

(thickness)
The thickness (after drying) of the easy-adhesion layer is preferably from 0.002 μm to 10.0 μm, more preferably 0.005 μm or more or 5 μm or less, among which 0.01 μm or more or 2 μm or less, and more preferably 0.01 μm or more. Alternatively, the thickness is more preferably 0.5 μm or less.
When the thickness of the easy-adhesion layer is in the above range, adhesion can be ensured, and deterioration of blocking, increase in haze, and the like can be suppressed.

<Intermediate buffer layer>
When the inorganic-containing layer and the easy-adhesion layer are provided, an intermediate buffer layer that absorbs surface irregularities of the inorganic-containing layer may be provided between the inorganic-containing layer and the easy-adhesion layer, if necessary.
The intermediate buffer layer is also called a top coat layer, and is a layer provided for the purpose of absorbing the surface irregularities of the inorganic-containing layer and suppressing yellowing or yellow-browning caused by the inorganic-containing layer.

The intermediate buffer layer is a layer containing (a) polyvinyl alcohol and (b) a silicon compound, and optionally contains (c) an ethylene-unsaturated carboxylic acid copolymer or (d) a crosslinking agent. preferable.
By providing the intermediate buffer layer, the haze value can be reduced, and the color tone and the transparency can be improved.

(Composition of the intermediate buffer layer)
The content ratio of (a) polyvinyl alcohol and (b) the silicon compound in the intermediate buffer layer is preferably 1/6 to 1/2, and more preferably 1/5 to 1 from the viewpoint of gas barrier properties and transparency. / 3 is more preferable.

The intermediate buffer layer preferably contains (a) 5 to 70% by mass, more preferably 10 to 30% by mass of polyvinyl alcohol from the viewpoint of gas barrier properties and print resistance.
In addition, from the viewpoint of high-speed gravure coating property, printing resistance, and hot water adhesion, it is preferable to contain (b) the silicon compound particles in an amount of 20 to 70% by mass, and in particular, at a ratio of 30% by mass or more or 60% by mass or less. More preferably, it is contained.
Further, from the viewpoint of gas barrier properties, high-speed gravure coating properties, and hot water adhesion, it is preferable that the ethylene-unsaturated carboxylic acid copolymer (c) contains 10 to 70% by mass, and more preferably 20% by mass or more or 60% by mass. % Is more preferable.
Further, from the viewpoint of hot water resistance, the crosslinking agent (d) preferably contains 2 to 30% by mass, more preferably 3% by mass or more or 10% by mass or less.

((A) polyvinyl alcohol)
Polyvinyl alcohol as a component of the intermediate buffer layer can be produced by a known method, and is usually obtained by saponifying a vinyl acetate polymer. The degree of saponification is preferably 80% or more, 90% or more, more preferably 95% or more, and particularly preferably 98% or more.

The average degree of polymerization of polyvinyl alcohol is usually from 200 to 3,500, and is preferably from 300 to 2,000, more preferably 500 or more, or 1500 or less, from the viewpoint of improving gas barrier properties, strength, and coatability.
Further, as the polyvinyl alcohol, a type obtained by copolymerizing ethylene at a ratio of 40% or less can be used, and a type carboxyl-modified can also be used.
The saponification degree and the average polymerization degree can be measured according to JIS K6726 (polyvinyl alcohol test method).
The aqueous polyvinyl alcohol solution can be prepared, for example, by supplying a polyvinyl alcohol resin in room temperature water while stirring and raising the temperature, followed by stirring at 80 to 95 ° C. for 30 to 60 minutes.

((B) silicon compound)
As the silicon compound, an oxide of silicon is preferable, and examples thereof include silicon dioxide particles, silicon oxide particles represented by SiOx, and silica sol. These may be used alone or in combination of two or more. May be used.
Note that X of SiOx is preferably larger than 1.0 and 2.0 or less.
The average particle size is preferably 0.5 nm to 2 μm from the viewpoint of hot water resistance and cohesive failure resistance, and particularly preferably 1 nm or more or 200 nm or less, and particularly preferably 100 nm or less.
The average particle diameter of the silicon compound particles can be measured, for example, by a method such as nitrogen gas adsorption (BET), observation with an electron microscope, small-angle X-ray scattering analysis, or dynamic light scattering. However, in the present invention, a value measured by a dynamic light scattering method is used.

The method for preparing the silicon compound particles is not particularly limited. For example, the method described in International Publication Pamphlet WO 95/17349, page 2, line 16 to page 10, line 26, or paragraphs [0012] to [0031] of JP-A-6-16414, specifically alkoxy It can be prepared by a method of hydrolyzing silane and aging it, or a method of dissolving water glass, ion-exchanging and concentrating.
The calculation of the functional group ratio in the case of the former preparation method can be carried out, for example, by the method described on page 15, line 19 to page 16, line 8 of the above-mentioned International Publication Pamphlet. It can be estimated as 100 mol%.

In general, regarding the use of alkoxysilane, it is known that a coating solution obtained by mixing a resin with alkoxysilane or a hydrolyzate thereof is applied to a film having an inorganic material-containing layer. However, since the cohesive stress is very strong, the inorganic substance-containing layer is rather damaged, and the gas barrier property is lowered. This tendency is particularly severe under hot water.
Interaction and coagulation with the resin component of the coating layer by using silica having a particle shape and preferably containing a silanol group by hydrolyzing and condensing the alkoxysilane and advancing the partial cross-linking reaction sufficiently to promote the partial crosslinking reaction. The power can be adjusted.

((C) ethylene-unsaturated carboxylic acid copolymer)
Ethylene-unsaturated carboxylic acid copolymer used as a component of the intermediate buffer layer, ethylene, acrylic acid, methacrylic acid, ethacrylic acid, fumaric acid, maleic acid, itaconic acid, monomethyl maleate, monoethyl maleate, anhydrous It is a copolymer with an unsaturated carboxylic acid such as maleic acid or itaconic anhydride, and among them, a copolymer of ethylene and acrylic acid or methacrylic acid is preferable from the viewpoint of versatility. The ethylene-unsaturated carboxylic acid copolymer may include any other monomers.

The proportion of the ethylene component in the ethylene-unsaturated carboxylic acid copolymer is preferably 65 to 90% by mass, and more preferably 70% by mass or more or 85% by mass or less from the viewpoint of versatility and flexibility. More preferred.
The proportion of the unsaturated carboxylic acid component is preferably from 10 to 35% by mass, more preferably 15% by mass or more or 30% by mass or less.

  Other monomer components that may be contained in the ethylene-unsaturated carboxylic acid copolymer include, for example, vinyl acetate, vinyl esters such as vinyl propionate, methyl acrylate, ethyl acrylate, isopropyl acrylate, Unsaturated carboxylic esters such as n-butyl acrylate, isobutyl acrylate, isooctyl acrylate, methyl methacrylate, isobutyl methacrylate, dimethyl maleate and diethyl maleate can be mentioned. -50% by mass. Such an ethylene-unsaturated carboxylic acid copolymer can be obtained by a known method, for example, a method such as radical polymerization under high temperature and high pressure.

From the viewpoint of gas barrier properties, adhesion, etc., the ethylene-unsaturated carboxylic acid copolymer preferably contains a neutralized product thereof, and the degree of neutralization of the neutralized product is from 10 to 100 from the viewpoint of gas barrier properties. % Is preferable, and especially, it is 20% or more and 100% or less, and more preferably 40% or more or 100% or less.
The degree of neutralization can be determined by the following equation.

Neutralization degree = (A / B) x 100 (%)
(A: mole number of neutralized carboxyl group in 1 g of neutralized ethylene-unsaturated carboxylic acid copolymer, B: carboxyl group in 1 g of ethylene-unsaturated carboxylic acid copolymer before neutralization Number of moles)
In the case of an aqueous dispersion, the above A is simply (the number of metal ions in the solvent) × (the valence of the metal ion), and the ethylene-unsaturated carboxylic acid copolymer before neutralizing B is used. It can be calculated as the number of carboxyl groups.

The ethylene-unsaturated carboxylic acid copolymer is, from the viewpoint of gas barrier properties, a dispersion medium containing the copolymer and at least one selected from ammonia, sodium hydroxide, potassium hydroxide, lithium hydroxide and the like. It is preferable to use an aqueous dispersion consisting of, based on the total number of carboxyl groups of the ethylene-unsaturated carboxylic acid copolymer, using the dispersion medium so that the degree of neutralization is the above value. preferable.
In order to produce an aqueous dispersion from the ethylene-unsaturated carboxylic acid copolymer and the dispersion medium, for example, a predetermined amount of water and both of the raw materials are supplied to a stirrable container, and a temperature of 90 to 150 ° C. For about 10 minutes to 2 hours. The aqueous dispersion thus obtained is excellent in stability, and does not significantly change in particle size and viscosity even when stored for a long period of time.

The ethylene-unsaturated carboxylic acid copolymer may further contain a divalent or trivalent metal. Such a divalent or trivalent metal can be introduced into the copolymer by adding it as an oxide when producing an aqueous dispersion together with a dispersion medium. Further, it can be introduced into the copolymer by adding it in the form of a metal carbonate or a metal sulfate other than the oxide. The compounding amount can be introduced at a ratio of 0 to 60 mol% based on the number of moles of the carboxyl group of the ethylene-unsaturated carboxylic acid copolymer.
The above ethylene-unsaturated carboxylic acid copolymer may be used alone or in combination of two or more.

((D) crosslinking agent)
By blending the crosslinking agent in the intermediate buffer layer, it is possible to improve the coating strength of the intermediate buffer layer and the adhesion to the base film and the like.

The crosslinking agent may be any compound that can react with the reactive functional group of the polyvinyl alcohol of the component (a) or the ethylene-unsaturated carboxylic acid copolymer of the component (b) to crosslink them. However, compounds having various groups corresponding to the reactive functional groups can be mentioned.
As the reactive functional group of the polyvinyl alcohol or the ethylene-unsaturated carboxylic acid copolymer, a carboxyl group or a salt-type carboxylic acid group, or other active hydrogen, depending on other components to be further copolymerized if desired. Various functional groups can be mentioned.
As the crosslinkable functional group in the crosslinker, a group capable of reacting with the above-mentioned polyvinyl alcohol or a reactive functional group of the ethylene-unsaturated carboxylic acid copolymer, for example, a carbodiimide group, an oxazoline group, an isocyanate group, an epoxy group, a methylol group Aldehyde group, acid anhydride group, aziridinyl group and the like, and carbodiimide group, oxazoline group, isocyanate group or epoxy group is preferable from the viewpoint of the stability of the mixed aqueous dispersion. One kind of these crosslinkable functional groups may be introduced in one molecule, or two or more kinds thereof may be introduced in one molecule. However, from the viewpoint of crosslinkability, the above-mentioned crosslinkable functional group is contained in two molecules in one molecule. It is preferable that more than one are introduced.

As the aqueous polymer having two or more oxazoline groups in the molecule, a polymer obtained by polymerizing an oxazoline group-containing monomer and an ethylenically unsaturated monomer used as needed can be used.
Here, as the oxazoline group-containing monomer, for example, 2-vinyl-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, Examples thereof include 2-isopropenyl-4-methyl-2-oxazoline and 2-isopropenyl-5-ethyl-2-oxazoline. These may be used alone or in combination of two or more. Among them, 2-isopropenyl-2-oxazoline is preferred because it is easily available industrially.

  As the cross-linking agent, an aqueous polymer having the above-described cross-linkable functional group is preferable, and is particularly excellent in reactivity with a carboxyl group or a salt-type carboxylic acid group of polyvinyl alcohol or an ethylene-unsaturated carboxylic acid copolymer, and is preferably used. An aqueous polymer having two or more oxazoline groups, carbodiimide groups, epoxy groups, isocyanate groups, or the like in a molecule that provides a crosslinked resin film having performance is more preferable.

(Method of forming intermediate buffer layer)
The intermediate buffer layer can be formed, for example, by the following method.
First, an aqueous dispersion containing (a) polyvinyl alcohol and (b) a silicon compound is prepared.
From the viewpoints of water vapor barrier properties, high-speed gravure coating properties, and hot water adhesion, it is desirable to further include (c) an ethylene-unsaturated carboxylic acid copolymer and (d) a crosslinking agent.
Then, the resin layer can be formed as an intermediate buffer layer by applying to the surface of the inorganic material-containing layer and drying.

  In the aqueous dispersion used for forming the intermediate buffer layer, (a) polyvinyl alcohol and (b) silicon compound particles, and if necessary, (c) ethylene so that the content in the resin layer becomes the above value. -It is preferable to contain each component of an unsaturated carboxylic acid copolymer and (d) a crosslinking agent.

  Various known additives can be added to the aqueous dispersion as needed. Examples of such additives include polyhydric alcohols such as glycerin, ethylene glycol, polyethylene glycol and polypropylene glycol, silane coupling agents, lower alcohols such as methanol, ethanol, normal propanol and isopropanol, ethylene glycol monomethyl ether and propylene glycol monomethyl. Ethers such as ether, propylene glycol diethyl ether, diethylene glycol monoethyl ether and propylene glycol monoethyl ether; esters such as propylene glycol monoacetate and ethylene glycol monoacetate; antioxidants; weather stabilizers; ultraviolet absorbers; Agents, pigments, dyes, antibacterial agents, lubricants, inorganic fillers, antiblocking agents, adhesives and the like.

  Further, the aqueous dispersion can be used by mixing with an aqueous dispersion of another resin. As such a resin aqueous dispersion, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, acrylic resin, acrylamide resin, methacrylamide resin, acrylonitrile resin, styrene-acrylic acid copolymer , Polyurethane, styrene-maleic acid copolymer, styrene-butadiene copolymer, high impact polystyrene resin, butadiene resin, polyester, acrylonitrile-butadiene copolymer, polyethylene, polyethylene oxide, propylene-ethylene copolymer, maleic anhydride Aqueous dispersions such as graft-propylene-ethylene copolymer, chlorinated polyethylene, chlorinated polypropylene, EPDM, phenolic resin, and silicone resin may be used alone or in combination of two or more.

  The method for preparing the aqueous dispersion is not particularly limited. For example, a method of dissolving each resin in water, adding a silicon compound particle or an aqueous liquid thereof, a crosslinking agent comprising an aqueous polymer having a crosslinkable functional group or an aqueous liquid thereof, an aqueous liquid of each resin and silicon Compound particles or an aqueous liquid thereof, a method of mixing a crosslinking agent comprising an aqueous polymer having a crosslinkable functional group or an aqueous liquid thereof, polymerizing each monomer in an aqueous polyvinyl alcohol solution, and then silicon compound particles or an aqueous liquid thereof, A method of adding a cross-linking agent comprising an aqueous polymer having a cross-linkable functional group or an aqueous liquid thereof, after polymerizing each monomer in an aqueous polyvinyl alcohol solution, neutralizing with an alkali, and then adding silicon compound particles or an aqueous liquid thereof And a method of adding a crosslinking agent comprising an aqueous polymer having a crosslinking functional group or an aqueous liquid thereof. In the above case, the mixture may be prepared using a solvent other than water such as alcohols.

  The coating liquid is preferably an aqueous coating liquid in view of the load on the environment due to the generation of VOCs (volatile organic compounds) and the health effects of workers. A known coating method such as a reverse roll coater, a gravure coater, a rod coater, an air doctor coater or a sprayer can be applied. Further, after forming the inorganic substance-containing layer on the present base film, it may be immersed in the aqueous dispersion.

(Thickness of intermediate buffer layer)
The thickness of the intermediate buffer layer is not particularly limited. It is preferably from 0.05 μm to 20 μm, more preferably from 0.1 μm to 10 μm, more preferably from 1 μm to 5 μm.

  Incidentally, the intermediate buffer layer may be subjected to a crosslinking treatment by irradiation with active energy rays such as electron beam irradiation, if necessary, in order to increase the water resistance and durability.

<Thickness of the protective film>
By adjusting the overall thickness of the present protective film, it is possible to suppress wrinkles and the like while ensuring light transmittance and light reflectivity.
From this viewpoint, the overall thickness of the present protective film is preferably 20 μm or more, more preferably 23 μm or more, or 500 μm or less, and particularly preferably 23 μm or more, or 250 μm or less.

<< Use of this protective film >>
As described above, the present protective film is an optical protective film having a special optical property of transmitting light incident from the particle-containing layer side while reflecting light incident from the opposite side to the particle-containing layer. Therefore, it can be suitably used as a constituent member of a backlight unit or a display device.

<Wavelength conversion film laminate>
For example, by laminating the present protective film with a phosphor sheet containing a phosphor and using it as a constituent member of a display device, the luminance of the display device can be improved. Specifically, as shown in FIG. 3, for example, the present protective film (“protective film (10)”) is provided on one of the front and back sides of a phosphor sheet (30) provided with a phosphor layer containing resin and phosphor 30A. The protective film (10) is laminated such that the present particle-containing layer (3) of the present invention is located on the opposite side of the phosphor sheet (30). (Referred to as “wavelength conversion film laminate”) (40).

  Regarding the present wavelength conversion film laminate, for example, as shown in FIG. 4, a structure in which a protective film (20) different from the protective film (10) is laminated on the front and back and the other side of the phosphor sheet (30). May be provided. At this time, the film haze of the protective film (10) is 50% or more, particularly 60% or more, while the film haze of the protective film (20) is less than 30%, especially less than 20%. it can.

  As shown in FIGS. 3 and 4, if the present wavelength conversion film laminate (40) is arranged on the viewing side of the light source (50) to constitute the backlight unit (100), the light source (50) can be viewed from the viewing side. The irradiated light beam passes through the present protective film (1) and is incident on the phosphor sheet (30), and the light beam excites the phosphor 30A to emit light in a 360-degree direction. Of the light rays, the light incident on the present protective film (10) side can be multiple-reflected by the present particle-containing layer (3) toward the phosphor sheet (30) side, so that the phosphor 30A is excited. To emit a light beam in a 360-degree direction. As described above, since the luminous efficiency of the phosphor sheet can be increased, the luminance of the display device can be improved.

As an example of the phosphor sheet provided with the phosphor layer containing the phosphor, a phosphor sheet provided with a quantum dot layer can be given. At this time, the “quantum dot layer” may be any layer containing a quantum dot, that is, a layer containing a nanoscale colloidal semiconductor, and a quantum dot film is a single-layer film containing a quantum dot, or the quantum dot layer. Any film may be used as long as it has a surface layer.
A preferred example of the quantum dot layer is a layer in which two or more types of quantum dots having different fluorescent properties are dispersed in a resin serving as a matrix. At this time, as the two or more types of quantum dots having different fluorescence characteristics, a quantum dot that emits fluorescence (red light) LR when excited by blue light LB and a fluorescence (green light) LG that is excited by blue light LB One example is a combination with a quantum dot that emits light. However, it is not limited to this combination.

  Since quantum dots deteriorate when exposed to oxygen or moisture, when using quantum dots, it is preferable to laminate a gas barrier layer or a water vapor barrier layer on one or both sides of the phosphor sheet (30).

  The thickness of the phosphor sheet made of the phosphor layer is preferably 10 to 250 μm, more preferably 25 μm or more and 125 μm or less, more preferably 38 μm or more or 100 μm or less.

<Backlight unit and display device>
A backlight unit or a display device can be formed using the present wavelength conversion film laminate.

(This backlight unit)
For example, as shown in FIGS. 3 and 4, the present wavelength conversion film laminate (40) is provided on the viewing side of the planar light source (50) to provide a backlight unit (referred to as “present backlight unit”). 100).
At this time, the protective film (10) is located on the light source side of the phosphor sheet (30), and in the protective film (10), the present particle-containing layer (3) is opposite to the phosphor sheet (30). It is necessary to arrange it so as to be located on the side, that is, the light source side.

If the backlight unit having such a structure (100), as shown in FIGS. 3 and 4, the surface light source primary beam L ₁ emitted from the (50), the protective film (1) transmitted is incident on the phosphor sheet (30), emits part of the primary light beam L secondary ray L ₂ 360 degrees direction phosphors 30A is excited by _one. Some of the secondary light beam L ₂ is incident on the protective film (10) side, the secondary ray L ₂ present particle-containing layer (3) is reflected by the phosphor sheet (30) side, a portion thereof There emit tertiary beam _{L 3} in the 360 degree direction by exciting phosphors 30A. Since multiple reflection can be performed by repeating such a process, the luminous efficiency of the phosphor sheet can be increased, and the luminance of the display device can be improved.

The planar light source may be of a direct type in which the light sources are arranged in a parallel plane on the side opposite to the viewing side of the present wavelength conversion film laminate. At this time, a diffusion plate or the like may be provided between the wavelength conversion film laminate and the light source, if necessary.
Further, the planar light source may be of an edge light type including a light source arranged on a peripheral side and a light guide plate for guiding primary light emitted from the light source to a viewing side to emit the primary light. .
In any case, a light emitting diode, a laser light source, or the like can be used as the light source.

The backlight unit may optionally include a known optical member.
For example, a retroreflective member may be provided so as to face the planar light source with the present wavelength conversion film laminate interposed therebetween. As the retroreflective member, a known diffusion plate, diffusion sheet, prism sheet, light guide plate, or the like can be used.
Further, a reflector may be provided so as to face the present wavelength conversion film laminate with the planar light source interposed therebetween. A well-known reflector can be used as the reflector.
More specifically, a prism sheet, a diffusion sheet, or both may be provided on the viewing side of the protective film (1) or (2). For example, if a prism sheet and a diffusion sheet are sequentially laminated on the viewing side of the protective film (2), light emitted from the light source passes through the protective film (1), the phosphor sheet (30) and the protective film (2). Then, the light is collected by the prism sheet and then diffused by the diffusion sheet.

As shown in FIG. 5, if the present wavelength conversion film laminate (40) is arranged on the viewing side of the planar light source (50), and the prism sheet (60) is further arranged on the viewing side, the above-described book bag can be obtained. in addition to the multiple reflection by the light unit (100), light L ₄ reflected toward the light source is incident from the light source side to the prism sheet (60), exciting the phosphor 30A incident on the phosphor sheet (30) to emits light _{L 5} in the direction of 360 degrees. Some of this light beam L ₅ represents incident on the protective film (10) side, the light beam L ₅ the particle-containing layer (3) is reflected by the phosphor sheet (30) side, a portion of the phosphor 30A the so that emits a light beam L ₆ to the excitation to 360 degree direction, cause further multiple reflection, it is possible to further increase the luminous efficiency of the phosphor sheet, it is possible to further improve the brightness of the display the display device.

(This display device)
The present backlight unit and a display unit, for example, a liquid crystal unit can be combined to form a display device (referred to as “present display device”), for example, a liquid crystal display device.

  At this time, the liquid crystal cell unit usually has a configuration in which two liquid crystal cells are sandwiched between polarizing plates.

  The display device further includes an optical compensation member for performing optical compensation as needed, a color filter substrate, a thin-layer transistor substrate, a lens film, a diffusion sheet, a hard coat layer, an anti-reflection layer, a low reflection layer, an anti-glare layer, and a front side. A scattering layer, a primer layer, an antistatic layer, an undercoat layer, an adhesive layer, and the like can be optionally provided.

<<<< description of phrase >>>>
In the present invention, the term “film” includes a “sheet”, and the term “sheet” includes a “film”.
Further, when expressed as a "panel" such as an image display panel or a protection panel, it includes a plate, a sheet, and a film.

In the present invention, when described as "X to Y" (X and Y are arbitrary numbers), "preferably larger than X" or "preferably Y" together with "X or more and Y or less" unless otherwise specified. The meaning of "smaller" is also included.
Further, when described as “X or more” (X is an arbitrary number), the meaning of “preferably larger than X” is included unless otherwise specified, and described as “Y or less” (Y is an arbitrary number). In this case, the meaning of “preferably smaller than Y” is also included unless otherwise specified.

Hereinafter, the present invention will be described specifically with reference to examples. However, the present invention is not limited at all by the following examples.
The measurement method and evaluation method used in the present invention are as follows.

(1) Intrinsic viscosity of polyester (dl / g)
1 g of the polyester was precisely weighed, dissolved in 100 ml of a mixed solvent of phenol / tetrachloroethane = 50/50 (weight ratio), and measured at 30 ° C.

(2) Average particle size of particles in polyester raw material (D50: μm)
The value of 50% integrated (weight basis) in the equivalent spherical distribution measured using a centrifugal sedimentation type particle size distribution analyzer (SA-CP3 manufactured by Shimadzu Corporation) was defined as the average particle size.

(3) Method of measuring thickness of coating layer (ILC) The surface of the coating layer was dyed with RuO ₄ and embedded in an epoxy resin. Thereafter, the section prepared by the ultrathin section method was stained with RuO ₄ again, and the cross section of the coating layer was measured using a transmission electron microscope (H-7650 manufactured by Hitachi, acceleration voltage 100 kV).

(4) Film haze and total light transmittance Haze and total light transmittance were measured using a haze meter HM-150 manufactured by Murakami Color Research Laboratory in accordance with JIS K 7136.

(5) Gas barrier properties (WvTR)
The water vapor barrier properties of the gas barrier films of the examples and the comparative examples are in accordance with the conditions of JIS Z0222 “Moisture Permeability Test Method of Moistureproof Packaging Container” and JIS Z0208 “Moisture Permeability Test Method of Moistureproof Packaging Material (Cup Method)”. Evaluation was made by the following method.
A urethane-based adhesive [AD900 and CAT-RT85 manufactured by Toyo Morton Co., Ltd .; = 10: 1.5 (weight ratio)], followed by drying to form an adhesive layer having a thickness of about 3 µm.
The gas barrier films of Examples and Comparative Examples were laminated on the adhesive layer such that the inorganic thin film layer side of the gas barrier films was adjacent to the adhesive layer, thereby obtaining a sample film for evaluating the water vapor barrier property.
Using two pieces of each sample film having a moisture permeable area of 10.0 cm × 10.0 cm square, a bag was prepared in which about 20 g of anhydrous calcium chloride was put as a hygroscopic agent and four sides were sealed, and the bag was heated at a temperature of 40 ° C. and a relative humidity of 90%. Put in a thermo-hygrostat and measure the mass (0.1mg unit) until 14 days as a measure of the weight increase almost every 48 hours or more, and calculate the water vapor transmission rate from the following formula. Item shown.
Water vapor transmission rate [g / m ² / day] = (m / s) / t
m: Increased mass (g) of the last two weighing intervals during the test period
s; moisture permeable area (m ² )
t: Time (h) / 24 (h) of the last two weighing intervals during the test period

(6) Thickness of inorganic-containing layer formed by vacuum deposition (PVD) The thickness of the inorganic-containing layer was measured using fluorescent X-rays. This method uses the phenomenon of emitting fluorescent X-rays specific to an atom when the atom is irradiated with X-rays. By measuring the intensity of the emitted fluorescent X-rays, the number (quantity) of the atoms can be determined. Can be. The X-ray fluorescence intensity of the measurement sample was measured in the same manner, and the film thickness was measured from the calibration curve.

(7) Thickness of Inorganic-Containing Layer Formed by Chemical Vapor Deposition (CVD) A sample was prepared by an ultra-thin section method embedded in an epoxy resin, and the cross section of the film was cut by a cross-sectional TEM device (JEM- manufactured by JEOL Ltd.). 1200 EXII) under the condition of an acceleration voltage of 120 KV.
Note that it is difficult to obtain an accurate value for the thickness of the CVD inorganic layer of 10 nm or less even in the measurement by the cross-sectional TEM method. Therefore, a relatively thick CVD inorganic layer of 20 nm or more formed under the same film forming conditions is used. Then, the film formation rate per unit traveling speed was calculated by measuring by a cross-sectional TEM method, and the thickness when the film was formed at the traveling speed described in the examples was calculated.

(8) Carbon Content of CVD Inorganic Material-Containing Layer Using an XPS analyzer K-Alpha manufactured by Thermo Fisher Scientific Co., Ltd., the binding energy was measured by XPS (X-ray photoelectron spectroscopy), and Si 2 _P , C 1 It was calculated elemental composition (at.%) by converting the area of the peak corresponding to _{S, N1 S,} O1 _S and the like. In addition, the carbon content of the CVD inorganic layer was evaluated by reading the value of the portion of the CVD inorganic layer on the XPS chart.

(9) Presence or absence of anti-Newton ring effect The presence or absence of anti-Newton ring effect of the gas barrier film was confirmed by the following evaluation method.
(Evaluation method)
The gas barrier film is cut into a size of 30 cm × 30 cm, placed on a light guide plate (BR-U10 manufactured by Bright Inc.), light from an LED light source is incident on the light guide plate, and the state of the film after 10 minutes is visually observed. By confirming, the presence or absence of the Newton ring was confirmed.
(Judgment criteria)
○ (good): There is an anti-Newton ring effect.
× (poor): No anti-Newton ring effect.

(10) Luminance evaluation A commercially available tablet terminal (Kindle Fire HDX7 ″ manufactured by Amazon) was disassembled, QDEF (quantum dot film manufactured by 3M) was removed from the backlight unit, and cut out into a rectangle instead of QDEF. A liquid crystal display device for evaluation was manufactured by incorporating a member having a laminate structure in which a protective film was bonded to the quantum dot-containing resin sheets of Examples and Comparative Examples, and then 760 mm in the vertical direction with respect to the surface of the light guide plate. Was measured by a luminance meter (manufactured by Konica Minolta: CA-2000) arranged at the position of, and when the luminance of the comparative example was set to a relative value of 100, judgment was made according to the following judgment criteria.
(Judgment criteria)
((Good): the relative value exceeds 100.
X (poor): relative value is 100 or less.

(11) Comprehensive evaluation Each protective film obtained in Examples and Comparative Examples was determined according to the following criteria.
(Judgment criteria)
（(Good): All of the items of gas barrier property, anti-Newton ring effect, and luminance are 輝 度.
Δ (little good): At least one of the items of gas barrier property, anti-Newton ring effect, and luminance is Δ, and the rest is Δ.
× (poor): At least one of the items of gas barrier property, anti-Newton ring effect, and luminance is ×.

  Various materials used in the examples and comparative examples were prepared as follows.

<Production method of polyester A>
Starting from 100 parts by weight of dimethyl terephthalate and 60 parts by weight of ethylene glycol, 0.09 parts by weight of magnesium acetate tetrahydrate was placed in a reactor as a catalyst, the reaction starting temperature was set to 150 ° C., and methanol was gradually distilled off. The reaction temperature was raised to 230 ° C. after 3 hours. After 4 hours, the transesterification reaction was substantially terminated. After adding 0.04 parts of ethyl acid phosphate to the reaction mixture, 0.04 parts of antimony trioxide was added, and a polycondensation reaction was performed for 4 hours. That is, the temperature was gradually raised from 230 ° C. to 280 ° C. On the other hand, the pressure was gradually reduced from the normal pressure, and finally was 0.3 mmHg. After the start of the reaction, the reaction was stopped at a time corresponding to the intrinsic viscosity of 0.63 dl / g due to a change in the stirring power of the reaction tank, and the polymer was discharged under nitrogen pressure. The intrinsic viscosity of the obtained polyester A was 0.63 dl / g.

<Production method of polyester B>
In the method for producing polyester A, 0.04 part of ethyl acid phosphate was added, and then 0.3 part of silica particles having an average particle diameter of 1.6 μm dispersed in ethylene glycol and 0.04 part of antimony trioxide were added. A polyester B was obtained using the same method as that for producing the polyester A, except that the polycondensation reaction was stopped at a time corresponding to an intrinsic viscosity of 0.65 dl / g. The obtained polyester B had an intrinsic viscosity of 0.65 dl / g.

<Production method of polyester C>
Polyester A was preliminarily crystallized at 160 ° C., and then subjected to solid-phase polymerization in a nitrogen atmosphere at a temperature of 220 ° C. to obtain Polyester C having an intrinsic viscosity of 0.85 dl / g.

<Production method of polyester film F1>
Polyester A / B = Layer A with a blending ratio of 90/10 (% by mass), Polyester A = Layer B with a blending ratio of 100 (% by mass), and each was supplied to two twin-screw extruders. After melting at 285 ° C., the layer A is the outermost layer (outer layer) and the layer B is an intermediate layer, and is co-extruded on a casting drum cooled to 20 ° C. in a two-layer, three-layer configuration, and cooled and solidified to form a non-oriented sheet. Obtained. Next, after stretching 3.4 times in the longitudinal direction at 90 ° C., performing a transverse stretching of 4.2 times at 125 ° C. through a preheating step in a tenter, and then performing a heat treatment at 235 ° C. for 5 seconds. At 160 ° C., 2.0% relaxation was applied in the width direction to obtain a polyester film F1 having a layer configuration of layer A / layer B / layer A = 2 μm / 19 μm / 2 μm and a thickness of 23 μm.

<Production method of polyester film F2>
Polyester C / B = 90/10 (% by mass) A layer, polyester A = 100 (% by mass) Except for using as raw material for layer B except for 100% (mass%). As a result, a polyester film F2 having an A layer / B layer / A layer = 2 μm / 19 μm / 2 μm and a thickness of 23 μm was obtained.

<Production method of polyester film F3>
In the polyester film F1, after the longitudinal stretching, before guiding the film to the tenter, the following anchor coat composition was prepared under the conditions of a blend ratio of oxazoline compound: resin A: resin B = 60% by mass: 20% by mass: 20% by mass. A polyester film F3 having the same layer structure as layer A / layer B / layer A / anchor coat layer was produced in the same manner as polyester film F1 except that the coating amount (after drying) was 0.1 g / m ^2. I got

・ Oxazoline compound:
Acrylic polymer epocloth having oxazoline groups and polyalkylene oxide chains (oxazoline group amount = 4.5 mmol / g, manufactured by Nippon Shokubai Co., Ltd.)
-Resin A (aqueous acrylic resin): A mixture of 40 parts by weight of ethyl acrylate, 30 parts by weight of methyl methacrylate, 20 parts by weight of methacrylic acid, and 10 parts by weight of glycidyl methacrylate is solution-polymerized in ethyl alcohol, and water is added after polymerization. While heating, ethyl alcohol was removed. The pH was adjusted to 7.5 with aqueous ammonia to obtain a water-based acrylic resin-based water-based paint.
-Resin B (aqueous urethane resin): First, a polyester polyol comprising 664 parts by mass of terephthalic acid, 631 parts by mass of isophthalic acid, 472 parts by mass of 1,4-butanediol, and 447 parts by mass of neopentyl glycol was obtained. Next, 321 parts by mass of adipic acid and 268 parts by mass of dimethylolpropionic acid were added to the obtained polyester polyol to obtain a pendant carboxyl group-containing polyester polyol A. Further, 160 parts by mass of hexamethylene diisocyanate was added to 1880 parts by mass of the polyester polyol A to obtain a water-based polyurethane resin water-based paint.

<Production method of polyester film F4>
In the polyester film F1, except that the following particle-containing layer composition is applied so that the application amount (after drying) is 0.1 g / m ² before guiding the film to the tenter after the longitudinal stretching, the polyester film F1 Similarly, a polyester film F4 having a layer structure of particle-containing layer / layer A / layer B / layer A was obtained.

(Particle-containing layer composition)
-Resin B (aqueous urethane resin): 60% by mass
The same as that used in the anchor coat layer of the polyester film F3.
-Oxazoline compound: 10% by mass
Acrylic polymer Epocloth having oxazoline groups and polyalkylene oxide chains (oxazoline group amount = 4.5 mmol / g, manufactured by Nippon Shokubai Co., Ltd.)
-Melamine compound: 10% by mass of hexamethoxymethylol melamine
Particles: 20% by mass of silica particles having an average particle size of 0.20 μm

[Example 1]
An anchor coat layer composition prepared as described below was applied on the polyester film F1 so that the applied amount (after drying) was 0.025 g / m ² , and dried to form an anchor coat layer.

(Preparation of anchor coating composition)
An isocyanate compound ("Coronate L" manufactured by Nippon Polyurethane Industry Co., Ltd.) and a saturated polyester ("Vylon 300" manufactured by Toyobo Co., Ltd., number average molecular weight: 23,000) are blended at a mass ratio of 1: 1 to form an anchor coating agent. Was prepared.

(Formation of PVD inorganic material-containing layer)
Then, using a vacuum evaporation apparatus, SiO (purity 99.9% or higher) was evaporated in a heating system, by introducing oxygen, an oxygen partial pressure of ^{3.5 × 10 -3 Pa, 5 ×} 10 -3 Under a vacuum of Pa, a PVD inorganic material-containing layer of SiOx having a thickness of 40 nm was formed on the anchor coat layer.

(Formation of intermediate buffer layer)
Further, the intermediate buffer layer composition prepared as described below was applied on the surface of the inorganic-containing layer by a gravure coating method (2.9 g / m ^{2 in a} wet state), dried with hot air at 90 ° C. for 5 seconds, and dried. A gas barrier film having an intermediate buffer layer (after drying) of 0.4 g / m ² was obtained.

(Preparation of intermediate buffer layer composition)
An aqueous dispersion is prepared by mixing (a), (b), (c) and (d), prepared as described below, so that the mixing ratio is 10: 30: 30: 30 (mass ratio). An intermediate buffer layer composition was prepared.
(A) Polyvinyl alcohol (PVA, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., “Gohsenol NM-14”, degree of saponification: 99% mol or more, degree of polymerization: 1400) is added to ion-exchanged water with stirring, and is heated at 95 ° C. for 60 minutes. After dissolution, a PVA aqueous liquid (a) having a solid content of 10% was prepared.
(B) Ethylene methacrylic acid copolymer (EMAA) (20% by weight of methacrylic acid, MFR: 300 g / 10 min), ammonia and ion-exchanged water were stirred and mixed at 95 ° C. for 2 hours, neutralization degree was 60%, solid content A 20% aqueous liquid (b) was prepared.
(C) According to the description in JP-A-6-16414, sodium water glass JIS3 was dissolved in an aqueous solution of sodium nitrate to prepare an aqueous solution of sodium silicate. Then, after passing through a hydrogen-type cation exchange resin column, a hydroxyl group-type anion exchange resin column, and a hydrogen-type cation exchange resin column again, an aqueous sodium hydroxide solution was added to obtain a silicic acid aqueous solution. Then, a 20% amount of the aqueous solution of silicic acid was distilled under reduced pressure to remove evaporated water, and the remaining aqueous solution of silicic acid was gradually supplied continuously to continuously perform vacuum distillation to produce a colloidal silica sol. The colloidal silica sol is passed through a hydrogen-type cation exchange resin column, a hydroxyl-type anion exchange resin column, and again a hydrogen-type cation exchange resin column. Immediately thereafter, special-grade ammonia water is added, and the pH is 9 and the average particle diameter is 4 nm. An aqueous silica sol (c) having a substance concentration of 500 ppm was prepared.
(D) In a flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer and dropping funnel, 179 parts by mass of deionized water and 2,2′-azobis (2-amidinopropane) dihydrochloride as a polymerization initiator were placed. 1 part by mass of the salt was charged and heated to 60 ° C. while gently flowing nitrogen gas, and 2 parts by mass of ethyl acrylate, 2 parts by mass of methyl methacrylate and 16 parts by mass of 2-isopropenyl-2-oxazoline were prepared therein. Was dropped from the dropping funnel in 1 hour. Thereafter, the reaction was carried out at 60 ° C. for 10 hours under a nitrogen stream, and after the reaction, the mixture was cooled to prepare a 2-oxazoline group-containing resin aqueous liquid (d) having a solid content of 10% by weight.

(Formation of easy adhesion layer)
The easily adhesive layer composition prepared as described below was blended so that A1 / U1 / C1 = 30/50/20 (% by mass), and adjusted to 10% by mass with a toluene solvent. Then, it applied and dried on the intermediate buffer layer so that application amount (after drying) might be set to 30 nm, and provided the easy adhesion layer.

(Preparation of easy adhesion layer composition)
The following were used as the easily adhesive layer composition.
(A1) Tetramethylol methane ethylene oxide-modified tetraacrylate (all ethylene glycol chains = 35). A tetrafunctional acrylate having a carbon-carbon double bond ratio of 5% by weight based on the whole.
(U1): Polyester urethane resin formed from isophorone diisocyanate: terephthalic acid: isophthalic acid: ethylene glycol: diethylene glycol: dimethylolpropanoic acid = 12: 19: 18: 21: 25: 5 (mol%).
(C1): Acrylic polymer epocloth having oxazoline groups and polyalkylene oxide chains (oxazoline group amount = 4.5 mmol / g, manufactured by Nippon Shokubai Co., Ltd.)

  As described above, a gas barrier film composed of the polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer was produced.

  Next, a particle-containing layer composition composed of the following particle-containing layer (A) composition is applied on the polyester film F1 of the gas barrier film by a bar coating method so that the thickness (after drying) becomes 3 μm. After drying, a particle-containing layer was provided to prepare a protective film comprising a particle-containing layer (A) / polyester film F1 / anchor coat layer / PVD inorganic substance-containing layer / intermediate buffer layer / adhesive layer.

(Particle-containing layer (A) composition)
Particles: Crosslinked acrylic beads (average particle size: 5 μm) 30 parts by mass Particles: Crosslinked acrylic beads (average particle size: 3 μm) 10 parts by mass Binder resin: acrylic polyol 42 parts by mass Curing agent: isocyanate 18 parts by mass Solvent: ethyl acetate 10 Parts by mass

  On the other hand, a mixture of AD900 and CAT-RT85 (manufactured by Toyo Morton Co., Ltd.) in a ratio of AD900: CAT-RT85 = 10: 1.5 (weight ratio) as a urethane-based adhesive is applied to one surface of the polyester film F1. Apply and then dry to provide an adhesive layer (thickness after drying is 3 μm), and further apply and dry an easy-adhesion layer on the other surface of the polyester film F1 so that the coating amount (after drying) is 30 nm. To form a laminated film consisting of an adhesive layer / polyester film F1 / easy adhesive layer.

  Then, a laminated film having a polyester film F1 / easy adhesion layer configuration is bonded so that the film F1 side is in contact with the adhesive base material layer, and the particle-containing layer (A) / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / A protective film having a configuration of an intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer was obtained.

(Formation of quantum dot layer composition film)
The quantum dot layer composition is applied on the easy-adhesion layer of the protective film so that the thickness after drying becomes 10 μm, and this is applied to the (quantum dot layer side) polyester film F1 / anchor coat layer / PVD inorganic material-containing After laminating with a barrier film composed of a layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer, the integrated amount of light is 1000 mJ / cm ² with a high-pressure mercury lamp 160 W from an ultraviolet irradiation device. By irradiating ultraviolet rays, the acrylic resin constituting the quantum dot layer composition is cured, and the particle-containing layer (A) / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / Adhesive layer / Polyester film F1 / Easy adhesion layer / Quantum dot layer / Polyester film F1 / Anchor coat layer / PVD To obtain a machine-containing layer / intermediate buffer layer / adhesion layer / adhesive layer / protective film laminate having the configuration of a polyester film F1 / adhesive layer.

・ Quantum dot-containing layer composition:
Quantum dot 1: CdSe / ZnS (emission peak: 530 nm) 2 parts by weight Quantum dot 2: CdSe / ZnS (emission peak: 620 nm) 2 parts by weight Dipentaerythritol pentaacrylate 63 parts by weight Nippon Kayaku KARAYAD R-128H 10 parts by weight ethylene Glycol-modified bisphenol A acrylate (ethylene glycol chain = 8) 20 parts by weight Diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide 3 parts by weight

[Example 2]
A particle-containing layer (B) / polyester film F1 was produced in the same manner as in Example 1, except that the following particle-containing layer (B) composition was used instead of the particle-containing layer (A) composition. / Anchor coat layer / PVD inorganic material-containing layer / Intermediate buffer layer / Easy adhesive layer / Adhesive layer / Polyester film F1 / Protective film consisting of an easily adhesive layer.

(Particle-containing layer (B) composition)
Particles: acrylic beads (average particle size: 6 μm) 20 parts by mass Particles: acrylic beads (average particle size: 3 μm) 10 parts by mass Binder resin: acrylic polyol 50 parts by mass Curing agent: isocyanate 20 parts by mass Solvent: ethyl acetate 30 parts by mass

  Next, in the same manner as in Example 1, the particle-containing layer (B) / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer / A protective film laminate having the structure of quantum dot layer / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer was obtained.

[Example 3]
A particle-containing layer (C) / polyester film F1 was produced in the same manner as in Example 1, except that the following particle-containing layer (C) composition was used instead of the particle-containing layer (A) composition. / Anchor coat layer / PVD inorganic material-containing layer / Intermediate buffer layer / Easy adhesive layer / Adhesive layer / Polyester film F1 / Protective film consisting of an easily adhesive layer.

(Particle-containing layer (C) composition)
Particles: acrylic beads (average particle size: 6 μm) 20 parts by mass Particles: acrylic beads (average particle size: 3 μm) 10 parts by mass Binder resin: acrylic polyol 50 parts by mass Curing agent: isocyanate 20 parts by mass Solvent: ethyl acetate 10 parts by mass

  Next, in the same manner as in Example 1, the particle-containing layer (C) / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer / A protective film laminate having the structure of quantum dot layer / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer was obtained.

[Example 4]
A particle-containing layer (A) / polyester film F2 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / easily adhesive layer was produced in the same manner as in Example 1 except that the polyester film F2 was used in Example 1. / Adhesive layer / polyester film F2 / protective film having the following structure:
Next, in the same manner as in Example 1, the particle-containing layer (C) / polyester film F2 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / easy adhesion layer / adhesion layer / polyester film F1 / easy adhesion layer / A protective film laminate having a structure of quantum dot layer / polyester film F2 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer was obtained.

[Example 5]
The same procedure as in Example 1 was carried out except that the polyester film F3 was changed to a polyester film F3 and an inorganic material-containing layer was provided on the in-line coat surface (corresponding to the anchor coat layer) of the polyester film F3. A) / a polyester film F3 / anchor coat layer / PVD inorganic substance-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F3 / adhesive layer
Next, in the same manner as in Example 1, the particle-containing layer (C) / polyester film F3 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F3 / adhesive layer / A protective film laminate having the structure of quantum dot layer / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer was obtained.

[Comparative Example 1]
A particle-containing layer (D) / polyester film F1 was produced in the same manner as in Example 1, except that the following particle-containing layer (D) composition was used instead of the particle-containing layer (A) composition. / Anchor coat layer / PVD inorganic material-containing layer / Intermediate buffer layer / Easy adhesive layer / Adhesive layer / Polyester film F1 / Protective film consisting of an easily adhesive layer.

(Particle-containing layer (D) composition)
Particles: Average particle size 2 μm Silica particles 5 parts by mass Binder: acrylic polyol 50 parts by mass Curing agent: isocyanate 10 parts by mass Solvent: ethyl acetate 30 parts by mass

  Next, in the same manner as in Example 1, the particle-containing layer (D) / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer / A protective film laminate having the structure of quantum dot layer / polyester film F1 / anchor coat layer / PVD inorganic material-containing layer / intermediate buffer layer / adhesive layer / adhesive layer / polyester film F1 / adhesive layer was obtained.

<Evaluation results>
The properties of each gas barrier film obtained in the above Examples and Comparative Examples are shown in Table 1 below.
In the table below, ILC is an abbreviation for in-line coating (application stretching method), and OLC is an abbreviation for off-line coating.

<Discussion>
From the results of the above example and the test conducted by the inventors, the optical protection film having the particle-containing layer on one side of the base film (the polyester film is used in the present example) has the light of the particle-containing layer. It has been found that the light transmittance and the reflectance can be selectively controlled by scattering the scattering property more than before. At this time, in the optical protective film, light incident from a film surface on which the particle-containing layer is not provided is more strongly reflected in the vicinity of the interface between the particle-containing layer and the base film layer directly in contact with the particle-containing layer. It is assumed that the optical characteristics can be controlled.
When the difference between the reflectance R2 of the film surface on the side opposite to the particle-containing layer and the reflectance R1 of the particle-containing layer-side surface is larger than 4%, when light is irradiated from the particle-containing layer surface side, By controlling the difference between the measured light transmittance T1 and the light transmittance T2 measured when light is irradiated from the side opposite to the particle-containing layer to be larger than 4%, the Newton ring phenomenon is prevented. It has been found that luminance can be improved while suppressing occurrence. In particular, for example, by arranging an optical protective film such that the opposite side to the particle-containing layer is located on the phosphor sheet side on one of the front and back sides of the phosphor sheet, the light emitted by the phosphor is It has been found that light incident on the particle-containing layer can be reflected to the phosphor sheet side, the luminous efficiency of the phosphor can be increased, and the luminance can be improved.

From the above examples and the test results conducted by the inventor, the present particle-containing layer shows that the particles are stacked like a stone wall, the particle density in a certain space volume is high, and the gap between the particles is as small as possible. It may be considered preferable to form a contiguous structure.
When light is incident on a general particle-containing layer, the light should travel straight as it should, but in the case of the present particle-containing layer, some light propagates between the particle interfaces that are in contact with each other, It is presumed that light is eventually scattered (reflected) at an angle close to the original direction.
Further, by mixing particles having a smaller average particle size, the particles are arranged so as to fill the gaps between the large particles, and it is presumed that finer light scattering is caused. Therefore, it can be inferred that the reflectance increased unexpectedly due to the synergistic effect of light scattering by particles having different sizes.

  Since the present particle-containing layer has special optical characteristics as described above, by providing an optical protective film having the present particle-containing layer on one side of a phosphor sheet, light emitted from a light source can be used for optical purposes. Since part of the light that is transmitted through the protective film and enters the phosphor sheet, and the phosphor itself emits omnidirectionally emits light toward the light source, the light that reaches the particle-containing layer in the same manner as described above is a particle. Small scattering at the interface. By repeating this multiple reflection, the light emitted by the various phosphors (red and green) in the phosphor sheet can be efficiently emitted (the sum of the transmittance and the reflectance is greater than 97%, so that the light is absorbed by light absorption and the like). It is suggested that the optical loss is small.

On the other hand, Comparative Example 1 suggests that a small optical loss may not necessarily contribute to the improvement in luminance.
Further, in the present invention, a two-sided asymmetric configuration (a side close to the light source), which is different from the conventional configuration (the conventional product has a configuration symmetrical on both sides; a film provided with a particle-containing layer on both sides), is provided via the phosphor sheet. It is also noteworthy that it was found that the use of a film having only a particle-containing layer) provided a significant effect of improving brightness.

  In the above example, the particle-containing layer is provided on one side of the front and back surfaces of the base film (1). However, in view of the above-mentioned mechanism of action, if the base film (1) is provided with the present particle-containing layer on the front and back surfaces, that is, on the light source side, the viewing side of the base film (1) Can be considered to be able to obtain the same effect even if it is arbitrary as long as the configuration is known as a configuration for optical use.

  The optical protective film of the present invention can have special optical characteristics, and particularly when used in combination with a phosphor sheet containing a phosphor such as a quantum dot, the occurrence of the Newton ring phenomenon can be suppressed. In addition, the luminance can be improved. Therefore, it can be suitably used as a component of various display devices such as a liquid crystal display (LCD).

Claims (14)

An optical protective film provided with a particle-containing layer on one of the front and back surfaces of a base film (1),
An optical protective film characterized in that the difference between the reflectance R2 of the film surface on the side opposite to the particle-containing layer and the reflectance R1 on the surface of the particle-containing layer is greater than 4%.   The difference between the light transmittance T1 measured when light is irradiated from the surface side of the particle-containing layer and the light transmittance T2 measured when light is irradiated from the side opposite to the particle-containing layer is greater than 4%. The optical protective film according to claim 1, wherein:   The optical protective film according to claim 1, wherein a film haze is greater than 40%, the reflectance R1 is less than 14%, and the reflectance R2 is greater than 14%.   The optical protective film according to any one of claims 1 to 3, wherein the light transmittance T1 is larger than 87%, and the light transmittance T2 is smaller than 85%.   5. The method according to claim 1, wherein a total value of the light transmittance T1 and the reflectance R1 is greater than 97%, and a total value of the light transmittance T2 and the reflectance R2 is greater than 97%. The optical protective film according to any one of the above. Water vapor transmission rate (WVTR) is 1g / ^{m 2} / day less than the optical protective film according to any one of claims 1 to 5.   The substrate film (1) is provided with a particle-containing layer on one side of the front and back surfaces, and the other side of the front and back surfaces of the base film (1) is provided with an adhesive layer and a substrate film (2). 3. The optical protective film according to item 1.   The optical protective film according to any one of claims 1 to 7, wherein each of the base film (1) and the base film (2) is a film containing polyester as a main component resin.   The optical protective film according to any one of claims 1 to 8, wherein the particle-containing layer is a layer containing a binder resin and particles having an average particle diameter of 3 µm to 10 µm.   The optical protective film according to claim 9, wherein the particle-containing layer contains particles having a particle size of 3 μm to 10 μm and particles having a particle size of 1 μm to 5 μm.   The optical protective film according to claim 10, wherein the particles having a particle size of 3 μm to 10 μm occupy 40 to 80% by mass of the particles contained in the particle-containing layer.   The optical protective film according to any one of claims 9 to 11, wherein the particle-containing layer contains 40 to 300 parts by mass of the particles with respect to 100 parts by mass of the binder resin.   The phosphor sheet according to any one of claims 1 to 12, wherein the particle-containing layer is located on a side opposite to the phosphor sheet on one side of the front and back sides of the phosphor sheet including the phosphor layer containing the resin and the phosphor. An optical film laminate having a configuration obtained by laminating the optical protective film (referred to as “protective film (10)”). An optical film laminate including a protective film (referred to as a “protective film (20)”) different from the protective film (10) on the front and back sides of the phosphor sheet,
The optical film laminate according to claim 13, wherein a film haze of the protective film (20) is less than 30%.

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